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two-weights-of-the-mass-m-1-and-m-2-m-1-are-joined-by-an-inextensible-string-of-negligible-mass-passing-over-a-fixed-frictionless-pulley-the-magnitude-1

two-weights-of-the-mass-m-1-and-m-2-m-1-are-joined-by-an-inextensible-string-of-negligible-mass-passing-over-a-fixed-frictionless-pulley-the-magnitude-1-12093

<div class="question">Two weights of the mass $m_{1}$ and $m_{2}\left(&gt;m_{1}\right)$ are joined by an inextensible string of negligible mass passing over a fixed frictionless pulley. The magnitude of the acceleration of the loads is</div>

['Physics', 'Laws of Motion', 'JEE Main']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$g$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\frac{m_{2}-m_{1}}{m_{2}} g$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{m_{1}}{m_{2}+m_{1}} g$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\frac{m_{2}-m_{1}}{m_{2}+m_{1}} g$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{m_{2}-m_{1}}{m_{2}+m_{1}} g$</span> </div>

<div class="solution">According to the question, we can draw the following diagram <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2019_phy_a9.png"/> <br/>Here, $T$ is the tension in the string. <br/>In equilibrium condition. <br/>For mass $m_{1}, \quad T-m_{1} g=m_{1} a$....(i) <br/>For mass $m_{2}, \quad m_{2} g-T=m_{2} a$....(ii) <br/>After adding Eqs. (i) and (ii), we get <br/>$$ <br/>\begin{aligned} <br/>m_{2} g-m_{1} g &amp;=m_{1} a+m_{2} a \\ <br/>\left(m_{2}-m_{1}\right) g &amp;=\left(m_{1}+m_{2}\right) a \\ <br/>a &amp;=\frac{\left(m_{2}-m_{1}\right)}{\left(m_{1}+m_{2}\right)} g <br/>\end{aligned} <br/>$$</div>

db\MarksBatch2_P3.db

two-weights-of-the-mass-m-1-and-m-2-m-1-are-joined-by-an-inextensible-string-of-negligible-mass-passing-over-a-fixed-frictionless-pulley-the-magnitude

two-weights-of-the-mass-m-1-and-m-2-m-1-are-joined-by-an-inextensible-string-of-negligible-mass-passing-over-a-fixed-frictionless-pulley-the-magnitude-97245

<div class="question">Two weights of the mass $m_{1}$ and $m_{2}\left(&gt;m_{1}\right)$ are joined by an inextensible string of negligible mass passing over a fixed frictionless pulley. The magnitude of the acceleration of the loads is</div>

['Physics', 'Laws of Motion', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$g$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\frac{m_{2}-m_{1}}{m_{2}} g$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{m_{1}}{m_{2}+m_{1}} g$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\frac{m_{2}-m_{1}}{m_{2}+m_{1}} g$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{m_{2}-m_{1}}{m_{2}+m_{1}} g$</span> </div>

<div class="solution">According to the question, we can draw the following diagram <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2019_phy_a9.png"/> <br/>Here, $T$ is the tension in the string. <br/>In equilibrium condition. <br/>For mass $m_{1}, \quad T-m_{1} g=m_{1} a$....(i) <br/>For mass $m_{2}, \quad m_{2} g-T=m_{2} a$....(ii) <br/>After adding Eqs. (i) and (ii), we get <br/>$$ <br/>\begin{aligned} <br/>m_{2} g-m_{1} g &amp;=m_{1} a+m_{2} a \\ <br/>\left(m_{2}-m_{1}\right) g &amp;=\left(m_{1}+m_{2}\right) a \\ <br/>a &amp;=\frac{\left(m_{2}-m_{1}\right)}{\left(m_{1}+m_{2}\right)} g <br/>\end{aligned} <br/>$$</div>

db\MarksBatch2_P3.db

two-wires-a-and-b-of-same-length-are-made-of-same-material-load-f-vs-elongation-x-graph-for-these-two-wires-is-shown-in-the-figure-then-which-of-the-f

two-wires-a-and-b-of-same-length-are-made-of-same-material-load-f-vs-elongation-x-graph-for-these-two-wires-is-shown-in-the-figure-then-which-of-the-f-39337

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/_IRs8XSqlH0Lgp6LzCpj8jLSxBkar6MeIIHge0eSpY8.original.fullsize.png"/><br/><br/>Two wires $A$ and $B$ of same length are made of same material. Load $(F)$ vs. elongation $(x)$ graph for these two wires is shown in the figure. Then which of the following statement(s) is / are true?</div>

['Physics', 'Mechanical Properties of Solids', 'WBJEE', 'WBJEE 2022']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">The cross-section area of $A$ is greater than that of $B$.</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Young's modulus of $A$ is greater than Young's modulus of $B$.</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">The cross-sectional area of $B$ is greater than that of $A$.</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">Young's modulus of both A and B are same.</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answers are: <span class="option-value">The cross-section area of $A$ is greater than that of $B$., Young's modulus of both A and B are same.</span> </div>

<div class="solution">same material have identical Young's Modulus.<br/>For a given strain and Young's Modulus.<br/>stress in same<br/>$$<br/>\begin{aligned}<br/>&amp;\frac{F_A}{A_A}=\frac{F_B}{A_B} \Rightarrow \frac{F_A}{F_B}=\frac{A_A}{A_B} \\<br/>&amp;\text { as } F_A&gt;F_B, A_A&gt;A_B<br/>\end{aligned}<br/>$$</div>

db\MarksBatch2_P3.db

two-wires-of-same-radius-having-lengths-l-1-and-i-2-and-resistivities-1-and-2-are-connected-in-series-the-equivalent-resistivity-will-be

two-wires-of-same-radius-having-lengths-l-1-and-i-2-and-resistivities-1-and-2-are-connected-in-series-the-equivalent-resistivity-will-be-53177

<div class="question">Two wires of same radius having lengths $l_{1}$ <br/>and $I_{2}$ and resistivities $\rho_{1}$ and $\rho_{2}$ are connected in series. The equivalent resistivity will be</div>

['Physics', 'Current Electricity', 'WBJEE', 'WBJEE 2016']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{\rho_{1} l_{2}+\rho_{2} I_{1}}{\rho_{1}+\rho_{2}}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\frac{\rho_{1} l_{1}+\rho_{2} /_{2}}{l_{1}+l_{2}}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{\rho_{1} l_{1}-\rho_{2} /_{2}}{l_{1}-l_{2}}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{\rho_{1} l_{2}+\rho_{2} l_{1}}{l_{1}+l_{2}}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{\rho_{1} l_{1}+\rho_{2} /_{2}}{l_{1}+l_{2}}$</span> </div>

<div class="solution">$R=\frac{\rho l}{A}$ <br/>where, $\rho=$ resistivity $l=$ length of the resistance wire $A=$ area of cross-section <br/>When the wires are connected in senes, then <br/>$$ <br/>\begin{aligned} <br/>R &amp;=R_{1}+R_{2} \\ <br/>R &amp;=\frac{\rho_{1} l_{1}}{A_{1}}+\frac{\rho_{2}l_{2}}{A_{2}} \\ <br/>R &amp;=\frac{\rho_{1} l_{1}}{A}+\frac{\rho_{2}l_{2}}{A} \\ <br/>\end{aligned} <br/>$$ <br/>$\mathrm{\rho}_{\mathrm{eq}}=$ resistivity of combination <br/>$$ <br/>\begin{array}{l} <br/>I=I_{1}+I_{2} \\ <br/>A=A <br/>\end{array} <br/>$$ <br/>Thus, $\rho_{\mathrm{eq}} \frac{I_{1}+I_{2}}{A}=\frac{\rho _{1}l_{1}+\rho_{2} l_{2}}{A}$ <br/>$$ <br/>\rho_{e q}=\frac{\rho_{1}l_{1}+\rho_{2} l_{2}}{I_{1}+I_{2}} <br/>$$</div>

db\MarksBatch2_P3.db

under-identical-conditions-the-s-n-1-reaction-will-occur-most-efficiently-with-1

under-identical-conditions-the-s-n-1-reaction-will-occur-most-efficiently-with-1-92997

<div class="question">Under identical conditions, the $\mathrm{S}_{\mathrm{N}} 1$ reaction will occur most efficiently with</div>

['Chemistry', 'General Organic Chemistry', 'JEE Main']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">tert-butyl chloride</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">1 -chlorobutane</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">2 -methyl- 1 -chloropropane</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">2 -chlorobutane</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">tert-butyl chloride</span> </div>

<div class="solution">$\mathrm{S}_{\mathrm{N}^{1}}$ reaction is most effective in $3^{\circ}$ carbon. <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_che_a29.png"/></div>

db\MarksBatch2_P3.db

under-identical-conditions-the-s-n-1-reaction-will-occur-most-efficiently-with

under-identical-conditions-the-s-n-1-reaction-will-occur-most-efficiently-with-13192

<div class="question">Under identical conditions, the $\mathrm{S}_{\mathrm{N}} 1$ reaction will occur most efficiently with</div>

['Chemistry', 'General Organic Chemistry', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">tert-butyl chloride</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">1 -chlorobutane</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">2 -methyl- 1 -chloropropane</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">2 -chlorobutane</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">tert-butyl chloride</span> </div>

<div class="solution">$\mathrm{S}_{\mathrm{N}^{1}}$ reaction is most effective in $3^{\circ}$ carbon. <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_che_a29.png"/></div>

db\MarksBatch2_P3.db

under-isothermal-conditions-two-soap-bubbles-of-radii-a-and-b-coalesce-to-form-a-single-bubble-of-radius-c-if-the-external-pressure-is-p-then-surface-

under-isothermal-conditions-two-soap-bubbles-of-radii-a-and-b-coalesce-to-form-a-single-bubble-of-radius-c-if-the-external-pressure-is-p-then-surface-84760

<div class="question">Under isothermal conditions, two soap bubbles of radii a and b coalesce to form a single bubble of radius c. If the external pressure is $\mathrm{P}$, then surface tension of the bubbles is</div>

['Physics', 'Mechanical Properties of Fluids', 'WBJEE', 'WBJEE 2021']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{\mathrm{P}\left(\mathrm{c}^{3}-\mathrm{a}^{3}+\mathrm{b}^{3}\right)}{4\left(\mathrm{a}^{2}+\mathrm{b}^{2}-\mathrm{c}^{2}\right)}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\frac{\mathrm{P}\left(\mathrm{c}^{3}-\mathrm{a}^{3}-\mathrm{b}^{3}\right)}{4\left(\mathrm{a}^{2}+\mathrm{b}^{2}-\mathrm{c}^{2}\right)}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{\mathrm{P}\left(\mathrm{c}^{2}+\mathrm{a}^{2}-\mathrm{b}^{2}\right)}{4\left(\mathrm{a}^{3}+\mathrm{b}^{3}-\mathrm{c}^{3}\right)}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{\mathrm{P}\left(\mathrm{c}^{3}+\mathrm{b}^{3}-\mathrm{c}^{3}\right)}{4\left(\mathrm{a}^{2}+\mathrm{b}^{2}-\mathrm{c}^{2}\right)}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{\mathrm{P}\left(\mathrm{c}^{3}-\mathrm{a}^{3}-\mathrm{b}^{3}\right)}{4\left(\mathrm{a}^{2}+\mathrm{b}^{2}-\mathrm{c}^{2}\right)}$</span> </div>

<div class="solution">Total number of moles $=$ constant <br/>$$ <br/>\begin{array}{l} <br/>\frac{P_{1} V_{1}}{R T}+\frac{P_{2} V_{2}}{R T}=\frac{P V}{R T} \Rightarrow P_{1} V_{1}+P_{2} V_{2}=P V \Rightarrow\left(P+\frac{4 T}{a}\right) \frac{4}{3} \pi a^{3}+\left(P+\frac{4 T}{b}\right) \frac{4}{3} \pi b^{3}=\left(P+\frac{4 T}{c}\right) \frac{4}{3} \pi c^{3} \\ <br/>\Rightarrow P\left(a^{3}+b^{3}-c^{3}\right)=4 T\left(c^{2}-a^{2}-b^{2}\right) \Rightarrow T=\frac{P\left(a^{3}+b^{3}-c^{3}\right)}{4\left(c^{2}-a^{2}-b^{2}\right)} \Rightarrow T=\frac{P}{4} \frac{\left(c^{3}-a^{3}-b^{3}\right)}{\left(a^{2}+b^{2}-c^{2}\right)} <br/>\end{array} <br/>$$</div>

db\MarksBatch2_P3.db

under-the-same-reaction-conditions-initial-concentration-of-1386-mol-dm-3-of-a-substance-becomes-half-in-40-s-and-20-s-through-firstorder-and-zeroorde

under-the-same-reaction-conditions-initial-concentration-of-1386-mol-dm-3-of-a-substance-becomes-half-in-40-s-and-20-s-through-firstorder-and-zeroorde-92055

<div class="question">Under the same reaction conditions, initial concentration of $1.386 \mathrm{~mol} \mathrm{dm}^{-3}$ of a substance becomes half in $40 \mathrm{~s}$ and 20 s through first-order and zero-order kinetics respectively. Ratio $\left(\frac{k_{1}}{k_{0}}\right)$ of the rate constants for first-order $\left(k_{1}\right)$ and zero-order $\left(\mathrm{k}_{0}\right)$ of the reactions is</div>

['Chemistry', 'Chemical Kinetics', 'WBJEE', 'WBJEE 2021']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$0.5 \mathrm{~mol}^{-1} \mathrm{dm}^{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$0.5 \mathrm{~mol} \mathrm{dm}^{-3}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$1.0 \mathrm{~mol} \mathrm{dm}^{-3}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$2.0 \mathrm{~mol}^{-1} \mathrm{dm}^{3}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$0.5 \mathrm{~mol}^{-1} \mathrm{dm}^{3}$</span> </div>

<div class="solution">For First order reaction <br/>$\mathrm{t}_{1 / 2}=\frac{0.693}{\mathrm{k}_{1}} \Rightarrow \mathrm{k}_{1}=\frac{0.693}{40} \mathrm{~s}^{-1}\quad_{-} \text {(i) }$ <br/>For Zero order reaction <br/>$\mathrm{t}_{1 / 2}=\frac{[\mathrm{R}]_{0}}{2 \mathrm{k}_{0}} \Rightarrow \mathrm{k}_{0}=\frac{1.386}{2 \times 20} \mathrm{~mol} / \mathrm{dm}^{3} / \mathrm{s} \quad_{-} \text {(ii) }$ <br/>$\underline{\text { Using (i) and (ii) }}$ <br/>$\frac{\mathrm{k}_{1}}{\mathrm{k}_{0}}=\frac{0.693 / 40}{1.386 / 2 \times 20}=\frac{0.693}{1.386}=0.5 \mathrm{~mol}^{-1}-\mathrm{dm}^{3}$</div>

db\MarksBatch2_P3.db

under-which-of-the-following-condition-is-the-relation-h-e-p-v-valid-for-a-closed-system

under-which-of-the-following-condition-is-the-relation-h-e-p-v-valid-for-a-closed-system-13115

<div class="question">Under which of the following condition is the relation $\Delta \mathrm{H}=\Delta \mathrm{E}+\mathrm{P} \Delta \mathrm{V}$ valid for a closed system?</div>

['Chemistry', 'Thermodynamics (C)', 'WBJEE', 'WBJEE 2009']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">Constant Pressure</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Constant temperature</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Constant temperature and pressure</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">Constant temperature, pressure and composition</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Constant Pressure</span> </div>

<div class="solution">This is applicable when pressure remains constant.</div>

db\MarksBatch2_P3.db

under-which-of-the-following-conditions-doesdo-the-system-of-equations-1-2-1-2-1-2-4-2-a-4-x-y-z-6-4-a-possesses-possess-unique-solution

under-which-of-the-following-conditions-doesdo-the-system-of-equations-1-2-1-2-1-2-4-2-a-4-x-y-z-6-4-a-possesses-possess-unique-solution-38474

<div class="question">Under which of the following condition(s) does(do) the system of equations $\left(\begin{array}{ccc}1 &amp; 2 &amp; 4 \\ 2 &amp; 1 &amp; 2 \\ 1 &amp; 2 &amp; (a-4)\end{array}\right)\left(\begin{array}{l}x \\ y \\ z\end{array}\right)=\left(\begin{array}{l}6 \\ 4 \\ a\end{array}\right)$ possesses (possess) unique solution?</div>

['Mathematics', 'Determinants', 'WBJEE', 'WBJEE 2022']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\forall \mathrm{a} \in \mathrm{R}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$a=8$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">for all integral values of a</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$a \neq 8$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$a \neq 8$</span> </div>

<div class="solution">$\Delta \neq 0$<br/>$\Rightarrow\left|\begin{array}{ccc}<br/>1 &amp; 2 &amp; 4 \\<br/>2 &amp; 1 &amp; 2 \\<br/>1 &amp; 2 &amp; \mathrm{a}-4<br/>\end{array}\right| \neq 0 \Rightarrow \mathrm{a} \neq 8$</div>

db\MarksBatch2_P3.db

underlinemathrmg-in-the-above-sequence-of-reactions-is

underlinemathrmg-in-the-above-sequence-of-reactions-is-64338

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/75dUMfi5RC3_pkEIu2xAm9DrTjZ5ByoZvFDx1fqM3-o.original.fullsize.png"/><br/><br/>' \(\underline{\mathrm{G}}\) ' in the above sequence of reactions is</div>

['Chemistry', 'Alcohols Phenols and Ethers', 'WBJEE', 'WBJEE 2023']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">\(\left(\mathrm{CH}_3\right)_2 \mathrm{CHCOOCH}_2 \mathrm{CH}_3\)</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{COOCH}_2 \mathrm{CH}_3\)</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{COOCH}_2 \mathrm{CH}_2 \mathrm{CH}_3\)</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{COOCH}\left(\mathrm{CH}_3\right)_2\)</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">\(\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{COOCH}_2 \mathrm{CH}_2 \mathrm{CH}_3\)</span> </div>

<div class="solution">Hint : <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/kpyHpn74EfUglOq1_B6BSzjL2lbawRgUy7giSrr1Fv4.original.fullsize.png"/><br/></div>

db\MarksBatch2_P3.db

upon-treatment-with-aloet-3-followed-by-usual-reactions-work-up-ch-3-cho-will-produce

upon-treatment-with-aloet-3-followed-by-usual-reactions-work-up-ch-3-cho-will-produce-40243

<div class="question">Upon treatment with Al(OEt) $_{3}$ followed by usual reactions (work up), CH $_{3} \mathrm{CHO}$ will produce</div>

['Chemistry', 'Aldehydes and Ketones', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">only $\mathrm{CH}_{3} \mathrm{COOCH}_{2} \mathrm{CH}_{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">a mixture of $\mathrm{CH}_{3} \mathrm{COOH}$ and ErOH</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">only $\mathrm{CH}_{3} \mathrm{COOH}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">only EtOH</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">only $\mathrm{CH}_{3} \mathrm{COOCH}_{2} \mathrm{CH}_{3}$</span> </div>

<div class="solution"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_che_a25.png"/></div>

db\MarksBatch2_P3.db

upon-treatment-with-i-2-and-aqueous-naoh-which-of-the-following-compounds-will-form-iodoform

upon-treatment-with-i-2-and-aqueous-naoh-which-of-the-following-compounds-will-form-iodoform-25683

<div class="question">Upon treatment with $I_{2}$ and aqueous $\mathrm{NaOH}$, which of the following compounds will form iodoform?</div>

['Chemistry', 'Alcohols Phenols and Ethers', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CHO}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COCH}_{2} \mathrm{CH}_{3}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \cdot \mathrm{CH}(\mathrm{OH}) \mathrm{CH}_{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \cdot \mathrm{CH}(\mathrm{OH}) \mathrm{CH}_{3}$</span> </div>

<div class="solution"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_che_a24.png"/></div>

db\MarksBatch2_P3.db

using-binomial-theorem-the-value-of-0999-3-correct-to-3-decimal-places-is

using-binomial-theorem-the-value-of-0999-3-correct-to-3-decimal-places-is-10675

<div class="question">Using binomial theorem, the value of $(0.999)^3$ correct to 3 decimal places is</div>

['Mathematics', 'Binomial Theorem', 'WBJEE', 'WBJEE 2009']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">0.999</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">0.998</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">0.997</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">0.995</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">0.997</span> </div>

<div class="solution">$$<br/>\begin{aligned}<br/>&amp; \text { Hints : }{ }^3 C_0-{ }^3 C_1(.001)+{ }^3 C_2(.001)^2-{ }^3 C_3(.001)^3 \\<br/>&amp; =1-.003+3(.000001)-(.000000001)=0.997<br/>\end{aligned}<br/>$$</div>

db\MarksBatch2_P3.db

value-of-tan-1-c-o-s-2-s-i-n-2-1-is

value-of-tan-1-c-o-s-2-s-i-n-2-1-is-94107

<div class="question">Value of $\tan ^{-1}\left(\frac{\sin 2-1}{\cos 2}\right)$ is</div>

['Mathematics', 'Inverse Trigonometric Functions', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{\pi}{2}-1$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$1-\frac{\pi}{4}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$2-\frac{\pi}{2}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{\pi}{4}-1$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$1-\frac{\pi}{4}$</span> </div>

<div class="solution">Hints : $\tan ^{-1}\left(\frac{\sin 2-1}{\cos 2}\right)=\tan ^{-1}\left(\frac{-(\sin 1-\cos 1)^2}{(\cos 1-\sin 1)(\cos 1+\sin 1)}\right) \quad=-\tan ^{-1}\left(\frac{\cos 1-\sin 1}{\cos 1+\sin 1}\right)=1-\frac{\pi}{4}$</div>

db\MarksBatch2_P3.db

vitamin-c-is

vitamin-c-is-84975

<div class="question">Vitamin $\mathrm{C}$ is</div>

['Chemistry', 'Biomolecules', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Citric acid</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Lactic acid</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Paracetamol</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">Ascorbic acid</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Ascorbic acid</span> </div>

<div class="solution">No Solution Available</div>

db\MarksBatch2_P3.db

water-is-flowing-in-streamline-motion-through-a-horizontal-tube-the-pressure-at-a-point-in-the-tube-is-p-where-the-velocity-of-flow-is-v-at-another-po

water-is-flowing-in-streamline-motion-through-a-horizontal-tube-the-pressure-at-a-point-in-the-tube-is-p-where-the-velocity-of-flow-is-v-at-another-po-22995

<div class="question">Water is flowing in streamline motion through a horizontal tube. The pressure at a point in the tube is $p$ where the velocity of flow is $v$. At another point, where the pressure is $p / 2,$ the velocity of flow is [density of water $=\rho]$</div>

['Physics', 'Mechanical Properties of Fluids', 'WBJEE', 'WBJEE 2013']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\sqrt{v^{2}+\frac{p}{\rho}}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\sqrt{v^{2}-\frac{p}{\rho}}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\sqrt{v^{2}+\frac{2 p}{\rho}}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\sqrt{v^{2}-\frac{2 p}{\rho}}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\sqrt{v^{2}+\frac{p}{\rho}}$</span> </div>

<div class="solution">As the water is flowing through the horizontal tube, so in the streamline flow of water, the sun of static pressure and dynamic pressure is constant $i, e$ <br/>$$ <br/>P+\frac{1}{2} \rho v^{2}=\frac{P}{2}+\frac{1}{2} \rho v_{1}^{2} <br/>$$ <br/>$\Rightarrow \quad v_{1}=\sqrt{\frac{P}{\rho}+v^{2}}$</div>

db\MarksBatch2_P3.db

water-is-flowing-through-a-very-narrow-tube-the-velocity-of-water-below-which-the-flow-remains-a-streamline-flow-is-known-as

water-is-flowing-through-a-very-narrow-tube-the-velocity-of-water-below-which-the-flow-remains-a-streamline-flow-is-known-as-15831

<div class="question">Water is flowing through a very narrow tube. The velocity of water below which the flow remains a streamline flow is known as</div>

['Physics', 'Mechanical Properties of Fluids', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">relative velocity</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">terminal velocity</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">critical velocity</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">particle velocity</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">critical velocity</span> </div>

<div class="solution">The velocity of water below which the flow remains streamline flow is known as critical velocity.</div>

db\MarksBatch2_P3.db

we-define-a-binary-relation-on-the-set-of-all-3-3-real-matrices-as-a-b-if-and-only-if-there-exist-invertible-matrices-p-and-q-such-that-b-p-a-q-1-the-

we-define-a-binary-relation-on-the-set-of-all-3-3-real-matrices-as-a-b-if-and-only-if-there-exist-invertible-matrices-p-and-q-such-that-b-p-a-q-1-the-31589

<div class="question">We define a binary relation - on the set of all $3 \times 3$ real matrices as $A \sim B,$ if and only if there exist invertible matrices $P$ and $Q$ such that $B=P A Q^{-1} .$ The binary relation $\sim$ is</div>

['Mathematics', 'Sets and Relations', 'WBJEE', 'WBJEE 2014']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">neither reflexive nor symmetric</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">reflexive and symmetric but not transitive</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">symmetric and transitive but not reflexive</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">an equivalence relation</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">an equivalence relation</span> </div>

<div class="solution">Let the relation defined as $R=\left\{(A, B): B=P A Q^{-1}\right\}$ <br/>For reflexive <br/>$A=I A I^{-1}$ <br/>$\Rightarrow(A, A) \in R$ <br/>$\Rightarrow R$ is reflexive <br/>For symmetric <br/>$\operatorname{Let}(A, B) \in R$ <br/>$\therefore B=P A Q^{-1}$ <br/>$\Rightarrow \quad B Q=P A\left(Q^{-1} Q\right)$ <br/>$\Rightarrow \quad B Q=P A$ <br/>$\Rightarrow \quad P^{-1}(B Q)=P^{-1} P(A)$ <br/>$\Rightarrow \quad P^{-1} B Q=A$ <br/>$\Rightarrow(B, A) \in R$ <br/>$\Rightarrow R$ is symmetric. <br/>For transitive Let $(A, B) \in R,(B, C) \in R$ <br/>Then, $\quad A=P B Q^{-1}$ and $B=R C S^{-1}$ <br/>$\Rightarrow \quad A=P R C S^{-1} Q^{-1}$ <br/>$\begin{array}{ll}\Rightarrow &amp; A=(P R) C(Q S)^{-1} \\ \Rightarrow &amp; (A, C) \in R\end{array}$ <br/>$\Rightarrow R$ is transitive. Hence, $R$ is an equivalence relation.</div>

db\MarksBatch2_P3.db

what-amount-of-clectricity-can-deposit-i-mole-of-al-metal-at-cathode-when-passed-through-molten-alcl-3

what-amount-of-clectricity-can-deposit-i-mole-of-al-metal-at-cathode-when-passed-through-molten-alcl-3-91280

<div class="question">What amount of clectricity can deposit <br/>I mole of Al metal at cathode when passed through molten $\mathrm{AlCl}_{3} ?$</div>

['Chemistry', 'Electrochemistry', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$0.3 \mathrm{F}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$1 \mathrm{F}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$3 \mathrm{F}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$1 / 3 \mathrm{F}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$3 \mathrm{F}$</span> </div>

<div class="solution">The number of electrons involved in the reaction are three as shown below <br/>$$ <br/>\mathrm{Al}^{3+}+3 e^{-} \longrightarrow \mathrm{Al} <br/>$$ <br/>It means the conversion of every aluminium ion to aluminium atom requires three electrons. Therefore, the amount of electricity required for one mole of $\mathrm{Al}^{3+}$ ions $=3 \mathrm{F}$.</div>

db\MarksBatch2_P3.db

what-current-will-flow-through-the-2-k-resistor-in-the-circuit-shown-in-the-figure-1

what-current-will-flow-through-the-2-k-resistor-in-the-circuit-shown-in-the-figure-1-20393

<div class="question">What current will flow through the $2 \mathrm{k} \Omega$ resistor in the circuit shown in the figure? <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_phy_q6.png"/></div>

['Physics', 'Current Electricity', 'JEE Main']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$3 \mathrm{mA}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$6 \mathrm{mA}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$12 \mathrm{mA}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$36 \mathrm{mA}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$3 \mathrm{mA}$</span> </div>

<div class="solution">From KCL we have <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_phy_a6.png"/> <br/> <br/>$i=\frac{72}{8 \times 10^{3}}=9 \times 10^{-3} \mathrm{A}$ <br/>$$ <br/>\begin{aligned} <br/>i \times 6 &amp;=(9-i) \times 3 \\ <br/>i &amp;=3 \mathrm{mA} <br/>\end{aligned} <br/>$$</div>

db\MarksBatch2_P3.db

what-current-will-flow-through-the-2-k-resistor-in-the-circuit-shown-in-the-figure

what-current-will-flow-through-the-2-k-resistor-in-the-circuit-shown-in-the-figure-32511

<div class="question">What current will flow through the $2 \mathrm{k} \Omega$ resistor in the circuit shown in the figure? <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_phy_q6.png"/></div>

['Physics', 'Current Electricity', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$3 \mathrm{mA}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$6 \mathrm{mA}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$12 \mathrm{mA}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$36 \mathrm{mA}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$3 \mathrm{mA}$</span> </div>

<div class="solution">From KCL we have <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2012_phy_a6.png"/> <br/> <br/>$i=\frac{72}{8 \times 10^{3}}=9 \times 10^{-3} \mathrm{A}$ <br/>$$ <br/>\begin{aligned} <br/>i \times 6 &amp;=(9-i) \times 3 \\ <br/>i &amp;=3 \mathrm{mA} <br/>\end{aligned} <br/>$$</div>

db\MarksBatch2_P3.db

what-is-obtained-when-nitrobenzene-is-treated-sequentially-with-i-nh-4-cl-zn-dust-and-ii-h-2-so-4-na-2-cr-2-o-7-1

what-is-obtained-when-nitrobenzene-is-treated-sequentially-with-i-nh-4-cl-zn-dust-and-ii-h-2-so-4-na-2-cr-2-o-7-1-75218

<div class="question">What is obtained when nitrobenzene is treated sequentially with (i) $\mathrm{NH}_4 \mathrm{Cl} / \mathrm{Zn}$ dust and (ii) $\mathrm{H}_2 \mathrm{SO}_4 / \mathrm{Na}_2 \mathrm{Cr}_2 \mathrm{O}_7$ ?</div>

['Chemistry', 'Hydrocarbons', 'JEE Main']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">meta-chloronitrobenzene</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">para-chloronitrobenzene</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">nitrosobenzene</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">benzene</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">nitrosobenzene</span> </div>

<div class="solution">Hints: <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/HN2lOs7vJZgH1Nv4ZDY5IVQlJd5vhR9vrV9eZL79m5U.original.fullsize.png"/><br/></div>

db\MarksBatch2_P3.db

what-is-obtained-when-nitrobenzene-is-treated-sequentially-with-i-nh-4-cl-zn-dust-and-ii-h-2-so-4-na-2-cr-2-o-7

what-is-obtained-when-nitrobenzene-is-treated-sequentially-with-i-nh-4-cl-zn-dust-and-ii-h-2-so-4-na-2-cr-2-o-7-62866

<div class="question">What is obtained when nitrobenzene is treated sequentially with (i) $\mathrm{NH}_4 \mathrm{Cl} / \mathrm{Zn}$ dust and (ii) $\mathrm{H}_2 \mathrm{SO}_4 / \mathrm{Na}_2 \mathrm{Cr}_2 \mathrm{O}_7$ ?</div>

['Chemistry', 'Hydrocarbons', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">meta-chloronitrobenzene</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">para-chloronitrobenzene</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">nitrosobenzene</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">benzene</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">nitrosobenzene</span> </div>

<div class="solution">Hints: <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/HN2lOs7vJZgH1Nv4ZDY5IVQlJd5vhR9vrV9eZL79m5U.original.fullsize.png"/><br/></div>

db\MarksBatch2_P3.db

what-is-the-correct-order-of-acidity-of-salicylic-acid-4hydroxybenzoic-acid-and-2-6-dihydroxybenzoic-acid

what-is-the-correct-order-of-acidity-of-salicylic-acid-4hydroxybenzoic-acid-and-2-6-dihydroxybenzoic-acid-50486

<div class="question">What is the correct order of acidity of salicylic acid, 4-hydroxybenzoic acid, and $2,6-$ dihydroxybenzoic acid?</div>

['Chemistry', 'Carboxylic Acid Derivatives', 'WBJEE', 'WBJEE 2022']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">2,6-dihydroxybenzoic acid &gt; salicylic acid &gt; 4-hydroxybenzoic acid</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">2,6-dihydroxybenzoic acid &gt; 4-hydroxybenzoic acid &gt; salicylic acid</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">salicylic acid &gt; 2, 6-dihydroxybenzoic acid &gt; 4-hydroxybenzoic acid</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">salicylic acid &gt; 4-hydroxybenzoic acid &gt; 2,6-dihydroxybenzoic acid</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">2,6-dihydroxybenzoic acid &gt; salicylic acid &gt; 4-hydroxybenzoic acid</span> </div>

<div class="solution"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/FmbqN947Br3Km8UOHvjxBhmQkcvzaFHtM-lUI4J_7nQ.original.fullsize.png"/><br/><br/>The conjugate base of 2, 6-dihydroxybenzoic acid is highly stabilised by $\mathrm{H}$-bonding. The effect is lesser in salicyclic acid.</div>

db\MarksBatch2_P3.db

what-is-the-current-i-shown-in-the-given-circuit

what-is-the-current-i-shown-in-the-given-circuit-24983

<div class="question">What is the current $I$ shown in the given circuit? <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2019_phy_q25.png"/></div>

['Physics', 'Current Electricity', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{V}{2 R}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\frac{V}{R}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$\frac{V}{16 R}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{V}{8 R}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{V}{16 R}$</span> </div>

<div class="solution">According to the question, <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2019_phy_a25.png"/> <br/>Total resistance of the given circuit <br/>$$ <br/>R_{\mathrm{eq}}=2 R <br/>$$ <br/>$\therefore \quad I=\frac{V / 2 R}{8} \quad\left(\because I_{1}=V / 2 R\right)$ <br/>So, current $I$ in the circuit $I=\frac{V}{16 R} \quad\left(\because I=\frac{I_{1}}{8}\right)$</div>

db\MarksBatch2_P3.db

what-is-the-edge-length-of-the-unit-cell-of-a-body-centred-cubic-crystal-of-an-element-whose-atomic-radius-is-75-mathrmpm

what-is-the-edge-length-of-the-unit-cell-of-a-body-centred-cubic-crystal-of-an-element-whose-atomic-radius-is-75-mathrmpm-70190

<div class="question">What is the edge length of the unit cell of a body centred cubic crystal of an element whose atomic radius is \(75 \mathrm{pm}\) ?</div>

['Chemistry', 'Solid State', 'WBJEE', 'WBJEE 2023']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">\(170 \mathrm{pm}\)</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">\(175 \mathrm{pm}\)</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">\(178 \mathrm{pm}\)</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">\(173.2 \mathrm{pm}\)</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">\(173.2 \mathrm{pm}\)</span> </div>

<div class="solution">Hint : In BCC, \(4 r=\sqrt{3} a\)<br/>\(\therefore \mathrm{a}=\frac{4 \mathrm{r}}{\sqrt{3}}=\frac{4 \times 75}{\sqrt{3}}=\frac{300}{\sqrt{3}}=\sqrt{3} \times 100 \mathrm{pm}=173.2 \mathrm{pm}\)</div>

db\MarksBatch2_P3.db

what-is-the-major-product-of-the-following-reaction-1

what-is-the-major-product-of-the-following-reaction-1-39280

<div class="question">What is the major product of the following reaction? <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/Bvifc3Ljvd4JKh4j-84vRpwE23bi0lRU93rs_vObRog.original.fullsize.png"/></div>

['Chemistry', 'Aldehydes and Ketones', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/bfX_CHCLuwedWXQInmg7WsJ8aPD517VPCqD5Seg3AGc.original.fullsize.png"/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/A0paJkFPU6zClHHw8FOgGSE44U4_x78igsCerP1Qig4.original.fullsize.png"/></span> </li><li class=""> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/uQUWWCoox4Vl3cAJMnl8M5t96_X3cVAyt5viFsbAqhQ.original.fullsize.png"/></span> </li><li class=""> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/IonlRzhf2DcBVeOiy1FpBeHcdOiAsELcx5eoT3_RmZY.original.fullsize.png"/></span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/bfX_CHCLuwedWXQInmg7WsJ8aPD517VPCqD5Seg3AGc.original.fullsize.png"/></span> </div>

<div class="solution">Hint: <br/>It's perkin reaction. The reaction starts with generation of nucleophile from propanoic anhydride as follows: <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/yrkmtfWOlrQyAGxlqZm8k56DvXk3VHBh7r7FnPbVZks.original.fullsize.png"/><br/> <br/>Then onwards, the nucleophile attacks the-CHO group as shown:<img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/O1okEVGCge4rAW0CzUohwsUFWhaL5-opxyATGcq30tk.original.fullsize.png"/><br/> <br/>Finally, it goes on to give:<img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/WrLCSxCpG264ztm4IGsqOsY4xYcT8mMWtOck5uKxzSc.original.fullsize.png"/></div>

db\MarksBatch2_P3.db

what-is-the-number-of-ways-in-which-an-examiner-can-assign-10-marks-to-4-questions-giving-not-less-than-2-marks-to-any-questions

what-is-the-number-of-ways-in-which-an-examiner-can-assign-10-marks-to-4-questions-giving-not-less-than-2-marks-to-any-questions-83602

<div class="question">What is the number of ways in which an examiner can assign 10 marks to 4 questions, giving not less than 2 marks to any questions?</div>

['Mathematics', 'Permutation Combination', 'WBJEE', 'WBJEE 2021']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">4</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">6</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">10</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">16</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">10</span> </div>

<div class="solution">$x_{1}+x_{2}+x_{3}+x_{4}=10 \quad x_{i} \geq 2$ <br/>$\Rightarrow\left(x_{1}-2\right)+\left(x_{2}-2\right)+\left(x_{3}-2\right)+\left(x_{4}-2\right)=2$ <br/>$\begin{array}{llll}\mathrm{y}_{1} &amp; \mathrm{y}_{2} &amp; \mathrm{y}_{3} &amp; \mathrm{y}_{4}\end{array}$ <br/>$\mathrm{y}_{1}+\mathrm{y}_{2}+\mathrm{y}_{3}+\mathrm{y}_{4}=2 ; \mathrm{y}_{i} \geq 0$ <br/>$\therefore$ N.O.W $={ }^{2+4-1} \mathrm{C}_{4-1}={ }^{5} \mathrm{C}_{3}=10$</div>

db\MarksBatch2_P4.db

what-is-the-particle-x-in-the-following-nuclear-reaction-4-9-be-2-4-he-6-12-c-x

what-is-the-particle-x-in-the-following-nuclear-reaction-4-9-be-2-4-he-6-12-c-x-93638

<div class="question">What is the particle $\mathrm{x}$ in the following nuclear reaction :<br/>${ }_4^9 \mathrm{Be}+{ }_2^4 \mathrm{He} \rightarrow{ }_6^{12} \mathrm{C}+\mathrm{x}$</div>

['Physics', 'Nuclear Physics', 'WBJEE', 'WBJEE 2009']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">electron</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">proton</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Photon</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">Neutron</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Neutron</span> </div>

<div class="solution">${ }_4^9 \mathrm{Be}+{ }_2^4 \mathrm{He} \rightarrow{ }_6^{12} \mathrm{C}+{ }_0^1 \mathrm{X}$<br/>Hence X represents neutron $\left({ }_0^1 n\right)$</div>

db\MarksBatch2_P4.db

what-is-the-phase-difference-between-two-simple-harmonic-motions-represented-by-x-1-a-sin-t-6-and-x-2-a-cos-t

what-is-the-phase-difference-between-two-simple-harmonic-motions-represented-by-x-1-a-sin-t-6-and-x-2-a-cos-t-80237

<div class="question">What is the phase difference between two simple harmonic motions represented by $x_{1}=A \sin \left(\omega t+\frac{\pi}{6}\right)$ and $x_{2}=A \cos (\omega t) ?$</div>

['Physics', 'Oscillations', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{\pi}{6}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\frac{\pi}{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{\pi}{2}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{2 \pi}{3}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{\pi}{3}$</span> </div>

<div class="solution">Given, <br/>$$ <br/>\begin{array}{l} <br/>x_{1}=A \sin \left(\omega t+\frac{\pi}{6}\right) \\ <br/>x_{2}=A \cos (\omega t) \\ <br/>x_{2}=A \operatorname{sin}\left(\omega t+\frac{\pi}{2}\right) <br/>\end{array} <br/>$$ <br/>Phase difference <br/>$$ <br/>\Delta \phi=\phi_{2}-\phi_{1} <br/>$$ <br/>$$ <br/>\begin{array}{l} <br/>\Delta \phi=\frac{\pi}{2}-\frac{\pi}{6} \\ <br/>\Delta \phi=\frac{3 \pi-\pi}{6}=\frac{\pi}{3} <br/>\end{array} <br/>$$</div>

db\MarksBatch2_P4.db

what-is-the-value-of-current-through-the-diode-in-the-circuit-given

what-is-the-value-of-current-through-the-diode-in-the-circuit-given-34520

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/R7VX4yotvHWhSjKc7LtE5rkdIekkfKSbORDzM7UnmzM.original.fullsize.png"/><br/> <br/>What is the value of current through the diode in the circuit given?</div>

['Physics', 'Semiconductors', 'WBJEE', 'WBJEE 2021']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$0 \mathrm{~mA}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$1 \mathrm{~mA}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$19 \mathrm{~mA}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$9 \mathrm{~mA}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$0 \mathrm{~mA}$</span> </div>

<div class="solution">Since diode is reverse biased</div>

db\MarksBatch2_P4.db

what-type-of-orbital-hybridisation-is-considered-on-p-in-pcl-5

what-type-of-orbital-hybridisation-is-considered-on-p-in-pcl-5-21009

<div class="question">What type of orbital hybridisation is considered on $\mathrm{P}$ in $\mathrm{PCl}_5$ ?</div>

['Chemistry', 'Chemical Bonding and Molecular Structure', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\mathrm{sp}^3 \mathrm{~d}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{dsp}^3$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{sp}^3 \mathrm{~d}^2$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\mathrm{d}^2 \mathrm{sp}^3$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{sp}^3 \mathrm{~d}$</span> </div>

<div class="solution">No Solution Available</div>

db\MarksBatch2_P4.db

what-will-be-current-through-the-200-resistor-in-the-given-circuit-a-long-time-after-the-switch-k-is-made-on

what-will-be-current-through-the-200-resistor-in-the-given-circuit-a-long-time-after-the-switch-k-is-made-on-51372

<div class="question">What will be current through the $200 \Omega$ <br/>resistor in the given circuit, a long time after the switch $K$ is made on? <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2018_phy_q2.png"/></div>

['Physics', 'Current Electricity', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Zero</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$100 \mathrm{mA}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$10 \mathrm{mA}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$1 \mathrm{mA}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$10 \mathrm{mA}$</span> </div>

<div class="solution">In steady state, arm having capacitors does not flow current. So, we can neglect them. <br/>$\therefore$ The given circuit reduces to <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2018_phy_a2.png"/> <br/> <br/>$$ <br/>R_{\text {net }}=200+400=600 \Omega <br/>$$ <br/>$\therefore$ Current in circuit, <br/>$$ <br/>\begin{aligned} <br/>I=\frac{V}{R} &amp;=\frac{6}{600}=0.01 \mathrm{A} \\ <br/>&amp;=10 \mathrm{mA} <br/>\end{aligned} <br/>$$</div>

db\MarksBatch2_P4.db

what-will-be-the-approximate-terminal-velocity-of-a-rain-drop-of-diameter-18-1-0-3-m-when-density-of-rain-water-1-0-3-kgm-3-and-the-coefficient-of-vis

what-will-be-the-approximate-terminal-velocity-of-a-rain-drop-of-diameter-18-1-0-3-m-when-density-of-rain-water-1-0-3-kgm-3-and-the-coefficient-of-vis-37038

<div class="question">What will be the approximate terminal velocity of a rain drop of diameter $1.8 \times 10^{-3} \mathrm{m}$, when density of rain water $\approx 10^{3} \mathrm{kgm}^{-3}$ and the coefficient of viscosity of air $\approx 1.8 \times 10^{-5} \mathrm{N}-sm^{-2}$ ? (Neglect buoyancy of air)</div>

['Physics', 'Mechanical Properties of Fluids', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$49 \mathrm{ms}^{-1}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$98 \mathrm{ms}^{-1}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$392 \mathrm{ms}^{-1}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$980 \mathrm{ms}^{-1}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$98 \mathrm{ms}^{-1}$</span> </div>

<div class="solution">Terminal velocity, $v=\frac{2}{9} r^{2} \frac{(\rho-\sigma)}{\eta}$ g <br/>Neglecting buoyancy effect of the fluid, $v=\frac{2}{9} \cdot \frac{\rho}{\eta} r^{2} g$ <br/>Putting the given values, we get $v=\frac{2}{9} \times \frac{10^{3} \times\left(0.9 \times 10^{-3}\right)^{2}}{1.8 \times 10^{-5}} \times 9.8=98 \mathrm{ms}^{-1}$</div>

db\MarksBatch2_P4.db

what-will-be-the-current-flowing-through-the-6-k-resistor-in-the-circuit-shown-where-the-breakdown-voltage-of-the-zener-is-6-v

what-will-be-the-current-flowing-through-the-6-k-resistor-in-the-circuit-shown-where-the-breakdown-voltage-of-the-zener-is-6-v-88838

<div class="question">What will be the current flowing through the $6 \mathrm{k} \Omega$ resistor in the circuit shown, where the breakdown voltage of the Zener is $6 \mathrm{V} ?$ <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2018_phy_q11.png"/></div>

['Physics', 'Semiconductors', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\frac{2}{3} m A$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$1 \mathrm{mA}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$10 \mathrm{mA}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{3}{2} m A$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{2}{3} m A$</span> </div>

<div class="solution"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2018_phy_a11.png"/> <br/> <br/>In the given circuit, the zener diode is used as a voltage regulating device. The voltage across $6 \mathrm{k} \Omega$ resistance is $(10-6) \mathrm{V}=4 \mathrm{V}$ <br/>Current through $6 \mathrm{k} \Omega$ resistor, $I=\frac{4 \mathrm{V}}{6 \mathrm{k} \Omega}=\frac{4}{6 \times 10^{3}}=\frac{2}{3} \times 10^{-3}=\frac{2}{3} \mathrm{mA}$</div>

db\MarksBatch2_P4.db

what-will-be-the-equivalent-resistance-between-the-terminals-a-and-b-of-the-infinite-resistive-network-shown-in-the-figure

what-will-be-the-equivalent-resistance-between-the-terminals-a-and-b-of-the-infinite-resistive-network-shown-in-the-figure-75644

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/0pQ3RxKvgmldkYk9fDfScYZWeU4V7U3Tqtr2WUYgx64.original.fullsize.png"/><br/> <br/>What will be the equivalent resistance between the terminals A and B of the infinite resistive network shown in the figure?</div>

['Physics', 'Current Electricity', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{(\sqrt{3}+1) \mathrm{R}}{2}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\frac{(\sqrt{3}-1) R}{2}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$3 \frac{R}{2}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$(\sqrt{3}+1) \mathrm{R}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$(\sqrt{3}+1) \mathrm{R}$</span> </div>

<div class="solution">Hint: <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/kOkTW84VK1gFCcyr4Tcx3FIl7YTFGbQgCJcC1KQxG1g.original.fullsize.png"/><br/> <br/>$x=2 R+\frac{R x}{R+x}$ <br/>$x^{2}-2 R x-2 R^{2}=0$ <br/>$x=(1+\sqrt{3}) R$</div>

db\MarksBatch2_P4.db

what-will-be-the-mass-of-one-atom-of-12-c

what-will-be-the-mass-of-one-atom-of-12-c-81833

<div class="question">What will be the mass of one atom of ${ }^{12} \mathrm{C}$ ?</div>

['Chemistry', 'Some Basic Concepts of Chemistry', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">1 a.m.u.</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$1.9923 \times 10^{-23} \mathrm{~g}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$1.6603 \times 10^{-22} \mathrm{~g}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">6 a.m.u.</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$1.9923 \times 10^{-23} \mathrm{~g}$</span> </div>

<div class="solution">Hint: <br/>Mass of 1 atom of ${ }^{12} \mathrm{C}=12$ a.m.u. $=12 \times 1.66 \times 10^{-24} \mathrm{~g}=1.9923 \times 10^{-23} \mathrm{~g}$</div>

db\MarksBatch2_P4.db

what-will-be-the-molar-specific-heat-at-constant-volume-of-an-ideal-gas-consisting-of-rigid-diatomic-molecules

what-will-be-the-molar-specific-heat-at-constant-volume-of-an-ideal-gas-consisting-of-rigid-diatomic-molecules-61341

<div class="question">What will be the molar specific heat at constant volume of an ideal gas consisting of rigid diatomic molecules?</div>

['Physics', 'Kinetic Theory of Gases', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{3}{2} R$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\frac{5}{2} R$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$R$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$3 R$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{5}{2} R$</span> </div>

<div class="solution">For a gas at temperature $T$, the internal energy, <br/>$$ <br/>U=\frac{f}{2} \mu R T <br/>$$ <br/>where, $f=$ degree of freedom <br/>$\Rightarrow$ Change in energy, $\Delta U=\frac{f}{2} \mu R \Delta T$ <br/>Also, as we know for any gas heat supplied at constant volume <br/>$$ <br/>\left(\Delta Q_{V}\right)=\mu C_{V} \Delta T=\Delta U <br/>$$ <br/>where, $C_{V}=$ molar specific heat at constant volume From Eqs. (i) and (ii), we get <br/>$$ <br/>C_{V}=\frac{1}{2} f R <br/>$$ <br/>For diatomic gas, degree of freedom, $f=5$ <br/>$$ <br/>C_{V}=\frac{5}{2} R <br/>$$</div>

db\MarksBatch2_P4.db

what-will-be-the-normality-of-the-salt-solution-obtained-by-neutralising-x-ml-y-n-hcl-with-y-ml-x-n-naoh-and-finally-adding-x-y-ml-distilled-water

what-will-be-the-normality-of-the-salt-solution-obtained-by-neutralising-x-ml-y-n-hcl-with-y-ml-x-n-naoh-and-finally-adding-x-y-ml-distilled-water-98380

<div class="question">What will be the normality of the salt solution obtained by neutralising $x$ mL. $y$ (N) HCl with $y \quad$ mL $x$ (N) $\mathrm{NaOH}$, and finally adding $(x+y) \mathrm{mL}$ distilled water</div>

['Chemistry', 'Some Basic Concepts of Chemistry', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{2(x+y)}{x y} N$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\frac{x y}{2(x+y)} N$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\left(\frac{2 x y}{x+y}\right) N$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\left(\frac{x+y}{x y}\right) N$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{x y}{2(x+y)} N$</span> </div>

<div class="solution">The reaction for given reaction is $\mathrm{HCl}+\mathrm{NaOH} \longrightarrow \mathrm{NaCl}+\mathrm{H}_{2} \mathrm{O}$ <br/>Number of moles xy xy 0 0 <br/>Added $\quad N V \quad N V$ <br/>Number of moles left 0 0 xy xy <br/>$\therefore N($ solution $)=\frac{\text { Number of milliequivalent }}{\text { vol. of solution in mililetre }}$</div>

db\MarksBatch2_P4.db

when-20-g-of-naphthoic-acid-c-11-h-8-o-2-is-dissolved-in-50-g-of-benzene-a-freezing-point-depression-of-2-k-is-observed-the-vant-hoff-factor-i-is-k-f-

when-20-g-of-naphthoic-acid-c-11-h-8-o-2-is-dissolved-in-50-g-of-benzene-a-freezing-point-depression-of-2-k-is-observed-the-vant-hoff-factor-i-is-k-f-47867

<div class="question">When $20 \mathrm{~g}$ of naphthoic acid $\left(\mathrm{C}_{11} \mathrm{H}_{8} \mathrm{O}_{2}\right)$ is dissolved in $50 \mathrm{~g}$ of benzene, a freezing point depression of $2 \mathrm{~K}$ is observed. The vant Hoff factor (i) is $\left[\mathrm{K}_{\mathrm{f}}=1.72^{\circ} \mathrm{K} \mathrm{kg} \mathrm{mol}^{-1}\right]$</div>

['Chemistry', 'Solutions', 'WBJEE', 'WBJEE 2021']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$0.5$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$1.0$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$2.0$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$3.0$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$0.5$</span> </div>

<div class="solution">$\begin{array}{l} <br/>\Delta \mathrm{T}_{\mathrm{f}}=\mathrm{i} \mathrm{K}_{\mathrm{f}} \mathrm{m} \\ <br/>2=\mathrm{i} \times 1.72 \times \frac{20 \times 1000}{172 \times 50} \\ <br/>\therefore \mathrm{i}=\frac{2}{0.01 \times 2 \times 200}=\frac{1}{2}=0.5 <br/>\end{array}$</div>

db\MarksBatch2_P4.db

when-100-g-of-boiling-water-at-10-0-c-is-added-into-a-calorimeter-containing-300-g-of-cold-water-at-1-0-c-temperature-of-the-mixture-becomes-2-0-c-the

when-100-g-of-boiling-water-at-10-0-c-is-added-into-a-calorimeter-containing-300-g-of-cold-water-at-1-0-c-temperature-of-the-mixture-becomes-2-0-c-the-56878

<div class="question">When $100 \mathrm{~g}$ of boiling water at $100^{\circ} \mathrm{C}$ is added into a calorimeter containing $300 \mathrm{~g}$ of cold water at $10^{\circ} \mathrm{C}$, temperature of the mixture becomes $20^{\circ} \mathrm{C}$. Then a metallic block of mass $1 \mathrm{~kg}$ at $10^{\circ} \mathrm{C}$ is dipped into the mixture in the calorimeter. After reaching thermal equilibrium, the final temperature becomes $19^{\circ} \mathrm{C}$. What is the specific heat of the metal in C.G.S. unit?</div>

['Physics', 'Thermal Properties of Matter', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$0.01$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$0.3$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$0.09$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$0.1$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$0.1$</span> </div>

<div class="solution">Hint: <br/>Let, heat capacity of calorimeter = ms <br/>$\begin{aligned} <br/>&amp; 100 \times 1 \times 80=300 \times 1 \times 10+\mathrm{ms} \times 10 \\ <br/>\therefore \mathrm{ms}=500 \mathrm{Cal} /{ }^{\circ} \mathrm{C} <br/>\end{aligned}$ <br/>Again, $(100+300) \times 1 \times 1+500 \times 1=1000 \times S_{b} \times 9$ <br/>$\therefore \mathrm{S}_{\mathrm{b}}=0.1 \mathrm{Cal} / \mathrm{g}^{\circ} \mathrm{C}$</div>

db\MarksBatch2_P4.db

when-a-60-mh-inductor-and-a-resistor-are-connected-in-series-with-an-ac-voltage-source-the-voltage-leads-the-current-by-6-0-if-the-inductor-is-replace

when-a-60-mh-inductor-and-a-resistor-are-connected-in-series-with-an-ac-voltage-source-the-voltage-leads-the-current-by-6-0-if-the-inductor-is-replace-35353

<div class="question">When a $60 \mathrm{mH}$ inductor and a resistor are connected in series with an AC voltage source, the voltage leads the current by $60^{\circ}$. If the inductor is replaced by a $0.5 \mu \mathrm{F}$ capacitor, the voltage lags behind the current by $30^{\circ} .$ What is the frequency of the AC supply?</div>

['Physics', 'Alternating Current', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\frac{1}{2 \pi} \times 10^{4} \mathrm{Hz}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\frac{1}{\pi} \times 10^{4} \mathrm{Hz}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{3}{2 \pi} \times 10^{4} \mathrm{Hz}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{1}{2 \pi} \times 10^{8} \mathrm{Hz}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{1}{2 \pi} \times 10^{4} \mathrm{Hz}$</span> </div>

<div class="solution">Given, inductance of inductor, $L=60 \mathrm{mH}$ <br/>$$ <br/>=60 \times 10^{-3} \mathrm{H} <br/>$$ <br/>Phase difference between voltage and current in $L-R$ circuit, $\theta_{1}=60^{\circ}$ <br/>Capacitance of capacitor, $C=0.5 \mu \mathrm{F}=0.5 \times 10^{-6} \mathrm{F}$ Phase difference between voltage and current in $\vec{R}-C$ circuit, $\theta_{2}=30^{\circ}$ <br/>For $L-R$ circuit. <br/>$$ <br/>\begin{array}{l} <br/>\tan \theta_{1}=\frac{X_{L}}{R} \\ <br/>\tan \theta_{1}=\frac{\omega L}{R} \quad \ldots(\mathrm{i})\left[\because X_{L}=\omega L\right] <br/>\end{array} <br/>$$ <br/>Similarly, for $R$ - $C$ circuit, <br/>$$ <br/>\tan \theta_{2}=\frac{X_{C}}{R} <br/>$$ <br/>$$ <br/>\tan \theta_{2}=\frac{\frac{1}{{\omega C}}}{R} \quad \ldots(\mathrm{ii})\left[\because X_{C}=\frac{1}{\omega C}\right] <br/>$$ <br/>From Eqs. (i) and (ii), we get <br/>$$ <br/>\begin{array}{l} <br/>\frac{\tan \theta_{1}}{\tan \theta_{2}}=\frac{\omega L}{R \times \frac{1}{\omega C R}}=\omega^{2} L C \\ <br/>\frac{\tan 60^{\circ}}{\tan 30^{\circ}}=\omega^{2} L C \\ <br/>\frac{\sqrt{3}}{1 / \sqrt{3}}=\omega^{2} L C \\ <br/>\omega^{2} L C=3 \\ <br/>\omega^{2}=\frac{3}{L C} \\ <br/>\omega^{2}=\frac{3}{60 \times 10^{-3} \times 0.5 \times 10^{-6}} \\ <br/>\omega^{2}=\frac{3}{30 \times 10^{-9}} \\ <br/>\omega=\sqrt{10^{8}} \\ <br/>\omega=10^{4} <br/>\end{array} <br/>$$ <br/>As we know that, <br/>$$ <br/>\omega=2 \pi f <br/>$$ <br/>$$ <br/>f=\frac{\omega}{2 \pi}=\frac{10^{4}}{2 \pi} \mathrm{Hz}=\frac{1}{2 \pi} \times 10^{4} \mathrm{Hz} <br/>$$</div>

db\MarksBatch2_P4.db

when-a-certain-metal-surface-is-illuminated-with-light-of-frequency-v-the-stopping-potential-for-photoelectric-current-is-v-0-when-the-same-surface-is

when-a-certain-metal-surface-is-illuminated-with-light-of-frequency-v-the-stopping-potential-for-photoelectric-current-is-v-0-when-the-same-surface-is-36598

<div class="question">When a certain metal surface is illuminated with light of frequency $v$, the stopping potential for photoelectric current is $V_{0}$. When the same surface is illuminated by light of frequency $\frac{v}{2}$ the stopping potential is $\frac{V_{0}}{4} .$ The threshold <br/>frequency for photoelectric, emission is</div>

['Physics', 'Dual Nature of Matter', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{v}{6}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\frac{v}{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\frac{2 v}{3}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{4 v}{3}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{v}{3}$</span> </div>

<div class="solution">Ist case <br/>$$ <br/>\begin{array}{l} <br/>h v=h v_{0}+e V_{0} \\ <br/>\frac{h v}{2}=h v_{0}+\frac{e V_{0}}{4} <br/>\end{array} <br/>$$ <br/>Solving Eqs. (i) and (ii), we get <br/>$$ <br/>v_{0}=\frac{v}{3} <br/>$$</div>

db\MarksBatch2_P4.db

when-a-dc-voltage-is-applied-at-the-two-ends-of-a-circuit-kept-in-closed-box-it-is-observed-that-the-current-gradually-increases-from-zero-to-a-certai

when-a-dc-voltage-is-applied-at-the-two-ends-of-a-circuit-kept-in-closed-box-it-is-observed-that-the-current-gradually-increases-from-zero-to-a-certai-46726

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/IT47_BpPG4TsYbLFXz8roz9CQCxzokYJP32oH7eMTXE.original.fullsize.png"/><br/> <br/>When a DC voltage is applied at the two ends of a circuit kept in closed box, it is observed that the current gradually increases from zero to a certain value and then remains constant. What do you think that the circuit contains?</div>

['Physics', 'Electromagnetic Induction', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">A resistor alone</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">A capacitor alone</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">A resistor and an inductor in series</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">A resistor and a capacitor in series</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">A resistor and an inductor in series</span> </div>

<div class="solution">Hint: <br/>LR circuit transient <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/Vx-pb4Ww6lb3QDCLzh8EYByxuW0hvoPWzQa6xkmoJuE.original.fullsize.png"/></div>

db\MarksBatch2_P4.db

when-a-manganous-salt-is-fused-with-a-mixture-of-kno-3-and-solid-naoh-the-oxidation-number-of-mn-changes-from-2-to

when-a-manganous-salt-is-fused-with-a-mixture-of-kno-3-and-solid-naoh-the-oxidation-number-of-mn-changes-from-2-to-31499

<div class="question">When a manganous salt is fused with a mixture of $\mathrm{KNO}_3$ and solid $\mathrm{NaOH}$ the oxidation number of Mn changes from +2 to</div>

['Chemistry', 'd and f Block Elements', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">+4</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">+3</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">+6</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">+7</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">+6</span> </div>

<div class="solution">$$<br/>\text { Hints : } \mathrm{Mn}^{+2}+\mathrm{NO}_3^{-}+\mathrm{O} \overline{\mathrm{H}} \rightarrow \stackrel{(+6)}{\mathrm{M} \mathrm{nO}_4^{-2}}+\mathrm{H}_2 \mathrm{O}<br/>$$</div>

db\MarksBatch2_P4.db

when-a-particle-executing-shm-oscillates-with-a-frequency-v-then-the-kinetic-energy-of-the-particle

when-a-particle-executing-shm-oscillates-with-a-frequency-v-then-the-kinetic-energy-of-the-particle-33729

<div class="question">When a particle executing SHM oscillates with a frequency $v$, then the kinetic energy of the particle</div>

['Physics', 'Oscillations', 'WBJEE', 'WBJEE 2014']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">changes periodically with a frequency of $v$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">changes periodically with a frequency of $2 \mathrm{v}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">changes periodically with a frequency of $\mathrm{v} / 2$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">remains constant</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">changes periodically with a frequency of $2 \mathrm{v}$</span> </div>

<div class="solution">We know that <br/>Kinetic energy $K=\frac{1}{2} m u^{2}$ <br/>where $u=\frac{d y}{d t}=\omega a \cos \omega t$ <br/>So. $K=\frac{1}{2} m \omega^{2} a^{2} \cos ^{2} \omega t$ <br/>Hence, kinetic energy varies periodically with double the frequency of SHM. So, when a particle executing SHM oscillates with a frequency v, then the kinetic energy of particle changes periodically with a frequency of $2 v$.</div>

db\MarksBatch2_P4.db

when-a-semiconducting-device-is-connected-in-series-with-a-battery-and-a-resistance-a-current-is-found-to-flow-in-the-circuit-if-however-the-polarity--1

when-a-semiconducting-device-is-connected-in-series-with-a-battery-and-a-resistance-a-current-is-found-to-flow-in-the-circuit-if-however-the-polarity-1-53635

<div class="question">When a semiconducting device is connected in series with a battery and a resistance, a current is found to flow in the circuit. If however, the polarity of the battery is reversed, practically no current flows in the circuit. The device may be</div>

['Physics', 'Semiconductors', 'JEE Main']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">a $p$ -type semiconductor</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">a $n$ -type semiconductor</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">an intrinsic semiconductor</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">a $p-n$ junction</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">a $p-n$ junction</span> </div>

<div class="solution">When the battery and resistance is connected with $p n$ diode, <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2017_phy_a26.png"/> <br/> <br/>In case of forward bias that $p$ is connected to + ve terminal of battery, current flows. If one reverse the polarity i.e., $p$ -end is made negative, no current flows in semiconductor diode.</div>

db\MarksBatch2_P4.db

when-a-semiconducting-device-is-connected-in-series-with-a-battery-and-a-resistance-a-current-is-found-to-flow-in-the-circuit-if-however-the-polarity-

when-a-semiconducting-device-is-connected-in-series-with-a-battery-and-a-resistance-a-current-is-found-to-flow-in-the-circuit-if-however-the-polarity-98097

<div class="question">When a semiconducting device is connected in series with a battery and a resistance, a current is found to flow in the circuit. If however, the polarity of the battery is reversed, practically no current flows in the circuit. The device may be</div>

['Physics', 'Semiconductors', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">a $p$ -type semiconductor</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">a $n$ -type semiconductor</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">an intrinsic semiconductor</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">a $p-n$ junction</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">a $p-n$ junction</span> </div>

<div class="solution">When the battery and resistance is connected with $p n$ diode, <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2017_phy_a26.png"/> <br/> <br/>In case of forward bias that $p$ is connected to + ve terminal of battery, current flows. If one reverse the polarity i.e., $p$ -end is made negative, no current flows in semiconductor diode.</div>

db\MarksBatch2_P4.db

when-a-spring-is-stretched-by-10-cm-the-potential-energy-stored-is-e-when-the-spring-is-stretched-by-10-cm-more-the-potential-energy-stored-in-the-spr

when-a-spring-is-stretched-by-10-cm-the-potential-energy-stored-is-e-when-the-spring-is-stretched-by-10-cm-more-the-potential-energy-stored-in-the-spr-53052

<div class="question">When a spring is stretched by $10 \mathrm{cm}$, the potential energy stored is $E$. When the spring is stretched by $10 \mathrm{cm}$ more, the potential energy stored in the spring becomes</div>

['Physics', 'Work Power Energy', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$2 E$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$4 E$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$6 E$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$10 E$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$4 E$</span> </div>

<div class="solution">For 1st situation, <br/>$$ <br/>E=\frac{1}{2} k\left(10 \times 10^{-2}\right)^{2} <br/>$$ <br/>For 2nd situation, <br/>$$ <br/>E^{\prime}=\frac{1}{2} k\left(20 \times 10^{-2}\right)^{2} <br/>$$ <br/>On comparing Eqs. (i) and (ii), we get <br/>$$ <br/>E^{\prime}=4 E <br/>$$</div>

db\MarksBatch2_P4.db

when-agcl-is-treated-with-kcn

when-agcl-is-treated-with-kcn-68468

<div class="question">When $\mathrm{AgCl}$ is treated with $\mathrm{KCN}$</div>

['Chemistry', 'Coordination Compounds', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{Ag}$ is precipitated</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">a complex ion is formed</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">double decomposition takes place</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">no reaction takes place</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">a complex ion is formed</span> </div>

<div class="solution">Hints: $\mathrm{AgCl}+2 \mathrm{KCN} \rightarrow \mathrm{K}\left[\mathrm{Ag}(\mathrm{CN})_2\right]+\mathrm{KCl}$</div>

db\MarksBatch2_P4.db

when-an-a-c-source-of-emf-e-with-frequency-100-hz-is-connected-across-a-circuit-the-phase-difference-between-e-and-current-i-in-the-circuit-is-observe-1

when-an-a-c-source-of-emf-e-with-frequency-100-hz-is-connected-across-a-circuit-the-phase-difference-between-e-and-current-i-in-the-circuit-is-observe-1-37656

<div class="question">When an $A C$ source of emf $E$ with frequency $\omega=100 \mathrm{~Hz}$ is connected across a circuit, the phase difference between<br/>$E$ and current I in the circuit is observed to be $\frac{\pi}{4}$ as shown in the figure. If the circuit consist of only $\mathrm{RC}$ or $\mathrm{RL}$ in series, then<br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/scgDMvLRCTaVROqZhcXm5lhCPNUh-IIFfpUDwYZCARI.original.fullsize.png"/></div>

['Physics', 'Alternating Current', 'JEE Main']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{C}=5 \mu \mathrm{F}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{L}=10 \mathrm{H}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{L}=1 \mathrm{H}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{C}=10 \mu \mathrm{F}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{C}=10 \mu \mathrm{F}$</span> </div>

<div class="solution">.. Since supply voltage lags the current $\operatorname{By}(\phi=\pi / 4)$<br/>$$<br/>\begin{aligned}<br/>&amp;\tan \phi=\frac{\mathrm{X}_{\mathrm{C}}}{\mathrm{R}}=1, \mathrm{X}_{\mathrm{C}}=\mathrm{R} \ldots \ldots(1) \\<br/>&amp;\mathrm{X}_{\mathrm{C}}=\frac{1}{\omega \mathrm{C}}=\frac{1}{100 \times 10 \times 10^{-6}}=1 \mathrm{k} \Omega=\mathrm{R}<br/>\end{aligned}<br/>$$</div>

db\MarksBatch2_P4.db

when-an-a-c-source-of-emf-e-with-frequency-100-hz-is-connected-across-a-circuit-the-phase-difference-between-e-and-current-i-in-the-circuit-is-observe

when-an-a-c-source-of-emf-e-with-frequency-100-hz-is-connected-across-a-circuit-the-phase-difference-between-e-and-current-i-in-the-circuit-is-observe-23926

<div class="question">When an $A C$ source of emf $E$ with frequency $\omega=100 \mathrm{~Hz}$ is connected across a circuit, the phase difference between<br/>$E$ and current I in the circuit is observed to be $\frac{\pi}{4}$ as shown in the figure. If the circuit consist of only $\mathrm{RC}$ or $\mathrm{RL}$ in series, then<br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/scgDMvLRCTaVROqZhcXm5lhCPNUh-IIFfpUDwYZCARI.original.fullsize.png"/></div>

['Physics', 'Alternating Current', 'WBJEE', 'WBJEE 2022']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{C}=5 \mu \mathrm{F}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{L}=10 \mathrm{H}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{L}=1 \mathrm{H}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{C}=10 \mu \mathrm{F}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{R}=1 \mathrm{k} \Omega, \mathrm{C}=10 \mu \mathrm{F}$</span> </div>

<div class="solution">.. Since supply voltage lags the current $\operatorname{By}(\phi=\pi / 4)$<br/>$$<br/>\begin{aligned}<br/>&amp;\tan \phi=\frac{\mathrm{X}_{\mathrm{C}}}{\mathrm{R}}=1, \mathrm{X}_{\mathrm{C}}=\mathrm{R} \ldots \ldots(1) \\<br/>&amp;\mathrm{X}_{\mathrm{C}}=\frac{1}{\omega \mathrm{C}}=\frac{1}{100 \times 10 \times 10^{-6}}=1 \mathrm{k} \Omega=\mathrm{R}<br/>\end{aligned}<br/>$$</div>

db\MarksBatch2_P4.db

when-aniline-is-nitrated-with-nitrating-mixture-in-ice-cold-condition-the-major-product-obtained-is

when-aniline-is-nitrated-with-nitrating-mixture-in-ice-cold-condition-the-major-product-obtained-is-10843

<div class="question">When aniline is nitrated with nitrating mixture in ice cold condition, the major product obtained is</div>

['Chemistry', 'Amines', 'WBJEE', 'WBJEE 2013']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$p$ -nitroaniline</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">2,4 dinitroaniline</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$o$ -nitroaniline</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$m$ nitroaniline</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$p$ -nitroaniline</span> </div>

<div class="solution">Direct nitration of aniline with nitric acid gives a complex mixture of mono, di- and tri-nitro compounds and oxidation products. If $-\mathrm{NH}_{2}$ group is protected by acetylation and then nitrated with nitrating mixture, $p$ -isomer is the main product. <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2013_che_a26.png"/></div>

db\MarksBatch2_P4.db

when-bacl-2-is-added-to-an-aqueous-salt-solution-a-white-precipitate-is-obtained-the-anion-among-co-3-2-so-3-2-and-so-4-2-that-was-present-in-the-solu

when-bacl-2-is-added-to-an-aqueous-salt-solution-a-white-precipitate-is-obtained-the-anion-among-co-3-2-so-3-2-and-so-4-2-that-was-present-in-the-solu-86444

<div class="question">When $\mathrm{BaCl}_{2}$ is added to an aqueous salt solution, a white precipitate is obtained. The anion among $\mathrm{CO}_{3}^{2-}, \mathrm{SO}_{3}^{2-}$ and $\mathrm{SO}_{4}^{2-}$ that was present in the solution can be</div>

['Chemistry', 'Practical Chemistry', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{CO}_{3}^{2-}$ but not any of the other two</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$S O_{3}^{2-}$ but not any of the other two</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{SO}_{4}^{2-}$ but not any of the other two</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">Any of them</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Any of them</span> </div>

<div class="solution">$\because$ If $\mathrm{CO}_{3}^{2-}, \mathrm{SO}_{3}^{2-}$ and $\mathrm{SO}_{4}^{2-}$ are present alongwith $\mathrm{BaCl}_{2}$, these can also show white precipitate (as precipitate of all these are also white ).</div>

db\MarksBatch2_P4.db

when-h-2-o-2-is-shaken-with-an-acidified-solution-of-k-2-cr-2-o-7-in-the-presence-of-ether-the-cthereal-layer-turns-blue-due-to-the-formation-of

when-h-2-o-2-is-shaken-with-an-acidified-solution-of-k-2-cr-2-o-7-in-the-presence-of-ether-the-cthereal-layer-turns-blue-due-to-the-formation-of-79194

<div class="question">When $\mathrm{H}_{2} \mathrm{O}_{2}$ is shaken with an acidified solution of $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ in the presence of ether, the cthereal layer turns blue due to the formation of</div>

['Chemistry', 'd and f Block Elements', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{Cr}_{2} \mathrm{O}_{3}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{CrO}_{4}^{2-}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{Cr}_{2}\left(\mathrm{SO}_{4}\right)_{3}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\mathrm{CrO}_{5}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{CrO}_{5}$</span> </div>

<div class="solution">$\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}+\mathrm{H}_{2} \mathrm{SO}_{4}+4 \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow$ $\mathrm{K}_{2} \mathrm{SO}_{4}+5 \mathrm{H}_{2} \mathrm{O}+2 \mathrm{CrO}_{5}$</div>

db\MarksBatch2_P4.db

when-light-is-refracted-from-a-surface-which-of-its-following-physical-parameters-does-not-change

when-light-is-refracted-from-a-surface-which-of-its-following-physical-parameters-does-not-change-27115

<div class="question">When light is refracted from a surface, which of its following physical parameters does not change?</div>

['Physics', 'Ray Optics', 'WBJEE', 'WBJEE 2015']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Velocity</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Amplitude</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">Frequency</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">Wavelength</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Frequency</span> </div>

<div class="solution">When light is refracted its frequency will remain unchanged.</div>

db\MarksBatch2_P4.db

when-light-of-frequency-v-1-is-incident-on-a-metal-with-work-function-w-where-h-v-1-w-then-photocurrent-falls-to-zero-at-a-stopping-potential-of-v-1-i

when-light-of-frequency-v-1-is-incident-on-a-metal-with-work-function-w-where-h-v-1-w-then-photocurrent-falls-to-zero-at-a-stopping-potential-of-v-1-i-12786

<div class="question">When light of frequency $v_{1}$ is incident on a metal with work function $W$ (where $h v_{1}&gt;w$ ), then photocurrent falls to zero at a stopping potential of $V_{1}$. If the frequency of light is increased to $v_{2},$ the stopping potential changes to $V_{2}$. Therefore, the charge of an electron is given by</div>

['Physics', 'Dual Nature of Matter', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\frac{W\left(v_{2}+v_{1}\right)}{v_{1} V_{2}+v_{2} V_{1}}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\frac{W\left(v_{2}+v_{1}\right)}{v_{1} V_{1}+v_{2} V_{2}}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$\frac{W\left(v_{2}-v_{1}\right)}{v_{1} V_{2}-v_{2} V_{1}}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\frac{W\left(v_{2}-v_{1}\right)}{v_{2} V_{2}-v_{1} V_{1}}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\frac{W\left(v_{2}-v_{1}\right)}{v_{1} V_{2}-v_{2} V_{1}}$</span> </div>

<div class="solution">From Einstein's photoelectric equation, <br/>$$ <br/>\begin{array}{l} <br/>h v=W+e V \\ <br/>W=\text { Work function } <br/>\end{array} <br/>$$ <br/>$v=$ Frequency of incident photon <br/>$V=$ Stopping potential <br/>For a photon of frequency $v_{1},$ <br/>$$ <br/>h v_{1}=W+e V_{1} <br/>$$ <br/>For photon of frequency $v_{2}$ <br/>$$ <br/>h v_{2}=W+e V_{2} <br/>$$ <br/>Divided Eq. (i) by Eq. (ii), <br/>$$ <br/>\begin{aligned} <br/>\frac{h v_{1}}{h v_{2}} &amp;=\frac{W+e V_{1}}{W+e V_{2}} \\ <br/>\frac{v_{1}}{v_{2}} &amp;=\frac{W+e V_{1}}{W+e V_{2}} <br/>\end{aligned} <br/>$$ <br/>$\Rightarrow W v_{1}+e V_{2} v_{1}=W v_{2}+e V_{1} v_{2}$ <br/>Solving above equation, $\Rightarrow \quad e=\frac{W\left(v_{2}-v_{1}\right)}{V_{2} v_{1}-V_{1} v_{2}}$</div>

db\MarksBatch2_P4.db

when-phenol-is-treated-with-d-2-so-4-d-2-o-some-of-the-hydrogens-get-exchanged-the-final-product-in-this-exchange-reaction-is

when-phenol-is-treated-with-d-2-so-4-d-2-o-some-of-the-hydrogens-get-exchanged-the-final-product-in-this-exchange-reaction-is-39385

<div class="question">When phenol is treated with $\mathrm{D}_{2} \mathrm{SO}_{4} / \mathrm{D}_{2} \mathrm{O},$ some of the hydrogens get exchanged. The final product in this exchange reaction is</div>

['Chemistry', 'General Organic Chemistry', 'WBJEE', 'WBJEE 2014']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_q47_opta.png"/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_q47_optb.png"/></span> </li><li class=""> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_q47_optc.png"/></span> </li><li class=""> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_q47_optd.png"/></span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_q47_opta.png"/></span> </div>

<div class="solution">In acidic medium, phenol exists in following resonating structures. <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_a47.png"/> <br/>Since, o/p positions are electron rich sites, so electrophile will attack on these site, i.e. hydrogen of these sites get exchanged by D (deuterium). Hence, the final product of the<img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2014_che_a47a.png"/></div>

db\MarksBatch2_P4.db

when-the-frequency-of-the-a-c-voltage-applied-to-a-series-lcr-circuit-is-gradually-increased-from-a-low-value-the-impedance-of-the-circuit

when-the-frequency-of-the-a-c-voltage-applied-to-a-series-lcr-circuit-is-gradually-increased-from-a-low-value-the-impedance-of-the-circuit-93568

<div class="question">When the frequency of the $A C$ voltage applied to a series LCR circuit is gradually increased from a low value, the impedance of the circuit</div>

['Physics', 'Alternating Current', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">monotonically increases</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">first increases and then decreases</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">first decreases and then increases</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">monotonically decreases</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">first increases and then decreases</span> </div>

<div class="solution">The impedance of LCR circuit $Z=\sqrt{R^{2}+\left(\omega_{c}-\frac{1}{\omega_{c}}\right)^{2}}$ <br/>Where, $R=$ Resistance $L=$ Inductance <br/>$C=$ Capacitance <br/>When frequency of AC voltage applied to a series LCR circuit, it will first increase and resonance state $\omega_{i}=\frac{1}{\omega_{c}},$ it will decrease. In that state $(Z=R),$ it will be minimum. So, it will first increases and then decreases.</div>

db\MarksBatch2_P4.db

when-the-frequency-of-the-light-used-is-changed-from-4-1-0-14-s-1-to-5-1-0-14-s-1-the-angular-width-of-the-principal-central-maximum-in-a-single-slit-

when-the-frequency-of-the-light-used-is-changed-from-4-1-0-14-s-1-to-5-1-0-14-s-1-the-angular-width-of-the-principal-central-maximum-in-a-single-slit-27634

<div class="question">When the frequency of the light used is changed from $4 \times 10^{14} \mathrm{s}^{-1}$ to $5 \times 10^{14} \mathrm{s}^{-1}$. the angular width of the principal (central) maximum in a single slit Fraunhoffer diffraction pattern changes by 0.6 radian. What is the width of the slit (assume that the experiment is performed in vacuum</div>

['Physics', 'Wave Optics', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$1.5 \times 10^{-7} \mathrm{m}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$3 \times 10^{-7} \mathrm{m}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$5 \times 10^{-7} \mathrm{m}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$6 \times 10^{-7} \mathrm{m}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$5 \times 10^{-7} \mathrm{m}$</span> </div>

<div class="solution">Given, initial frequency of light, <br/>$$ <br/>f_{1}=4 \times 10^{14} \mathrm{s}^{-1} <br/>$$ <br/>Final frequency of light, $f_{2}=5 \times 10^{14} \mathrm{s}^{-1}$ <br/>Change in wavelength $, \Delta \lambda=\lambda_{1}-\lambda_{2}$ <br/>or <br/>$$ <br/>\Delta \lambda=\frac{c}{f_{1}}-\frac{c}{f_{2}} <br/>$$ <br/>$$ <br/>\begin{array}{l} <br/>=\frac{3 \times 10^{8}}{4 \times 10^{14}}-\frac{3 \times 10^{8}}{5 \times 10^{14}} \\ <br/>=\frac{3 \times 10^{8}}{10^{14}}\left(\frac{1}{4}-\frac{1}{5}\right) \\ <br/>=\frac{3 \times 10^{8}}{10^{14}} \times \frac{1}{20} \\ <br/>=1.5 \times 10^{-7} \mathrm{m} <br/>\end{array} <br/>$$ <br/>Now, we know that, Angular width of central maxima, <br/>$$ <br/>\begin{array}{l} <br/>\theta=\frac{2 \lambda}{d} \text { or } \Delta \theta=\frac{2 \Delta \lambda}{d} \\ <br/>d=\frac{2 \Delta \lambda}{\Delta \theta} <br/>\end{array} <br/>$$ <br/>Here, $\Delta \theta=0.6$ radian <br/>$$ <br/>d=\frac{2 \times 1.5 \times 10^{-7}}{0.6}=5 \times 10^{-7} \mathrm{m} <br/>$$</div>

db\MarksBatch2_P4.db

when-the-value-of-r-in-the-balanced-nheatstone-bridge-shown-in-the-figure-is-increased-from-5-to-7-the-value-of-shas-to-increased-by-3-in-order-to-mai

when-the-value-of-r-in-the-balanced-nheatstone-bridge-shown-in-the-figure-is-increased-from-5-to-7-the-value-of-shas-to-increased-by-3-in-order-to-mai-81566

<div class="question">When the value of $R$ in the balanced Nheatstone bridge, shown in the figure, is increased from $5 \Omega$ to $7 \Omega$, the value of shas to increased by $3 \Omega$ in order to maintain the palance. What is the initial values of $S$ ? <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2019_phy_q26.png"/></div>

['Physics', 'Current Electricity', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$2.5 \Omega$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$3 \Omega$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$5 \Omega$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$7.5 \Omega$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$7.5 \Omega$</span> </div>

<div class="solution">According to the balanced condition of Wheatstone bridge. <br/>In the first case, <br/>$$ <br/>\begin{array}{l} <br/>\frac{P}{Q}=\frac{R}{S} \\ <br/>\frac{P}{Q}=\frac{5}{S}....(i) <br/>\end{array} <br/>$$ <br/>In the second case <br/>$$ <br/>\frac{P}{Q}=\frac{7}{S+3}....(ii) <br/>$$ <br/>From Eqs. (i) and (ii), we get <br/>$\begin{aligned} \frac{5}{S} &amp;=\frac{7}{S+3} \\ 5(S+3) &amp;=7 S \\ 5 S+15 &amp;=7 S \\ 2 S &amp;=15 \\ S &amp;=7.5 \Omega \end{aligned}$</div>

db\MarksBatch2_P4.db

which-atomic-species-cannot-be-used-as-a-nuclear-fuel

which-atomic-species-cannot-be-used-as-a-nuclear-fuel-86278

<div class="question">Which atomic species cannot be used as a nuclear fuel?</div>

['Chemistry', 'd and f Block Elements', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">${ }_{92}^{233} U$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">${ }_{92}^{235} U$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">${ }_{94}^{239} \mathrm{Pu}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">${ }_{92}^{238} U$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">${ }_{92}^{238} U$</span> </div>

<div class="solution">Among the given options, ${ }_{92} \mathrm{U}^{238}$ is an isotope of uranium but cannot be used as a nuclear-fuel. U- 238 is non-fissile, i.e., it does not undergo fission by thermal neutrons. The energy released when U-238 absorbs a neutron is insufficient to carry out nuclear fission. Hence, (d) is the correct option.</div>

db\MarksBatch2_P4.db

which-information-below-regarding-this-reaction-is-applicable-1

which-information-below-regarding-this-reaction-is-applicable-1-91982

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/1X5Rib5rqxArK7UKVaSa9DbqK6vZM1mO1qfH75EiQ-c.original.fullsize.png"/><br/> <br/>Which information below regarding this reaction is applicable?</div>

['Chemistry', 'Haloalkanes and Haloarenes', 'JEE Main']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">It follows $\mathrm{S}_{\mathrm{N}} 2$ pathway, because it is a primary alkyl chloride.</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">It follows $S_{N} 1$ pathway, because the intermediate carbocation is resonance stabilized.</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{S}_{\mathrm{N}} 1$ pathway is not followed, because the intermediate carbocation is destabilised by $-1$ effect of oxygen</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">A mixed $\mathrm{S}_{\mathrm{N}} 1$ and $\mathrm{S}_{\mathrm{N}} 2$ pathway is followed.</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">A mixed $\mathrm{S}_{\mathrm{N}} 1$ and $\mathrm{S}_{\mathrm{N}} 2$ pathway is followed.</span> </div>

<div class="solution">Hint: <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/LSMlRvFXlsi5I9waaTJM8BTzXCVhV8Oe4FLCR0iuZTU.original.fullsize.png"/><br/> <br/>$\mathrm{S}_{\mathrm{N}} 2$ is also facilitated by OH due to resonance stablization of transition state.</div>

db\MarksBatch2_P4.db

which-information-below-regarding-this-reaction-is-applicable

which-information-below-regarding-this-reaction-is-applicable-27695

<div class="question"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/1X5Rib5rqxArK7UKVaSa9DbqK6vZM1mO1qfH75EiQ-c.original.fullsize.png"/><br/> <br/>Which information below regarding this reaction is applicable?</div>

['Chemistry', 'Haloalkanes and Haloarenes', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">It follows $\mathrm{S}_{\mathrm{N}} 2$ pathway, because it is a primary alkyl chloride.</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">It follows $S_{N} 1$ pathway, because the intermediate carbocation is resonance stabilized.</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{S}_{\mathrm{N}} 1$ pathway is not followed, because the intermediate carbocation is destabilised by $-1$ effect of oxygen</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">A mixed $\mathrm{S}_{\mathrm{N}} 1$ and $\mathrm{S}_{\mathrm{N}} 2$ pathway is followed.</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">A mixed $\mathrm{S}_{\mathrm{N}} 1$ and $\mathrm{S}_{\mathrm{N}} 2$ pathway is followed.</span> </div>

<div class="solution">Hint: <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/LSMlRvFXlsi5I9waaTJM8BTzXCVhV8Oe4FLCR0iuZTU.original.fullsize.png"/><br/> <br/>$\mathrm{S}_{\mathrm{N}} 2$ is also facilitated by OH due to resonance stablization of transition state.</div>

db\MarksBatch2_P4.db

which-of-the-following-arrangements-is-correct-in-respect-of-solubility-in-water

which-of-the-following-arrangements-is-correct-in-respect-of-solubility-in-water-62710

<div class="question">Which of the following arrangements is correct in respect of solubility in water?</div>

['Chemistry', 'Practical Chemistry', 'WBJEE', 'WBJEE 2016']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{CaSO}_{4}&gt;\mathrm{BaSO}_{4}&gt;\mathrm{BeSO}_{4}&gt;\mathrm{MgSO}_{4}&gt;\mathrm{SrSO}_{4}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\mathrm{BeSO}_{4}&gt;\mathrm{MgSO}_{4}&gt;\mathrm{CaSO}_{4}&gt;\mathrm{SrSO}_{4}&gt;\mathrm{BaSO}_{4}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{BaSO}_{4}&gt;\mathrm{Sr} \mathrm{SO}_{4}&gt;\mathrm{CaSO}_{4}&gt;\mathrm{MgSO}_{4}&gt;\mathrm{BeSO}_{4}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\mathrm{BeSO}_{4}&gt;\mathrm{CaSO}_{4}&gt;\mathrm{MgSO}_{4}&gt;\mathrm{SrSO}_{4}&gt;\mathrm{BaSO}_{4}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{BeSO}_{4}&gt;\mathrm{MgSO}_{4}&gt;\mathrm{CaSO}_{4}&gt;\mathrm{SrSO}_{4}&gt;\mathrm{BaSO}_{4}$</span> </div>

<div class="solution">The correct order of solubility of sulphates in water is <br/>$\mathrm{BeSO}_{4}&gt;\mathrm{MgSO}_{4}&gt;\mathrm{CaSO}_{4}&gt;\mathrm{SrSO}_{4}&gt;\mathrm{BaSO}_{4}$ <br/>Solublity of 2nd group sulphates decreases as we down the group due to less release of hydration energy. $\mathrm{Be}^{2+} &lt; \mathrm{Mg}^{2+} &lt; \mathrm{Ca}^{2+} &lt; \mathrm{Sr}^{2+} &lt; \mathrm{Ba}^{24}$ (lonic Size) <br/>As hydration energy decreases more rapidly than latice energy, the solubility decreases down the group. Hydration Energy $=\frac{\text { Charge }}{\text { Size }}$ <br/>While lathice energy almost remains constant. Hence, solubility decreases.</div>

db\MarksBatch2_P4.db

which-of-the-following-atoms-should-have-the-highest-1-electron-affinity

which-of-the-following-atoms-should-have-the-highest-1-electron-affinity-65991

<div class="question">Which of the following atoms should have the highest $1^{\prime \prime}$ electron affinity?</div>

['Chemistry', 'Classification of Elements and Periodicity in Properties', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">F</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">0</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{N}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">C</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">F</span> </div>

<div class="solution">$\because$ F-atom has 2 nd highest electron affinity <br/>(Cl has highest) in the periodic table <br/>$\therefore$ Among the given options F-has highest electron gain affinity</div>

db\MarksBatch2_P4.db

which-of-the-following-carbocations-will-be-most-stable

which-of-the-following-carbocations-will-be-most-stable-27332

<div class="question">Which of the following carbocations will be most stable?</div>

['Chemistry', 'General Organic Chemistry', 'WBJEE', 'WBJEE 2009']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\mathrm{Ph}_3 \mathrm{C}^{++}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{CH}_3-\stackrel{+}{\mathrm{C}} \mathrm{H}_3$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\left(\mathrm{CH}_3\right)_2 \stackrel{+}{\mathrm{C}} \mathrm{H}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\mathrm{CH}_2=\mathrm{CH}-\stackrel{+}{\mathrm{C}} \mathrm{H}_2$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{Ph}_3 \mathrm{C}^{++}$</span> </div>

<div class="solution">Hints: <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/khdJ9i8w1kbTz6FG-MFKtpEDjCsEoVVqIiIxbYNXjd8.original.fullsize.png"/><br/><br/>(Highly resonance stabilized)</div>

db\MarksBatch2_P4.db

which-of-the-following-chemicals-may-be-used-to-identify-three-unlabelled-beakers-containing-concnaoh-conc-h-2-so-4-and-water

which-of-the-following-chemicals-may-be-used-to-identify-three-unlabelled-beakers-containing-concnaoh-conc-h-2-so-4-and-water-16640

<div class="question">Which of the following chemicals may be used to identify three unlabelled beakers containing conc.NaOH, conc.$\mathrm{H}_{2}\mathrm{SO}_{4}$ and water?</div>

['Chemistry', 'Practical Chemistry', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\mathrm{NH}_{4} \mathrm{NO}_{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{NaCl}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$\left(\mathrm{NH}_{4}\right)_{2} \mathrm{CO}_{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">HCOONa</span> </li> </ul>

<div class="correct-answer"> The correct answers are: <span class="option-value">$\mathrm{NH}_{4} \mathrm{NO}_{3}$, $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{CO}_{3}$</span> </div>

<div class="solution">$\mathrm{NH}_{4} \mathrm{NO}_{3}$ will evolve $\mathrm{NH}_{3}$ pungent smelling gas with $\mathrm{NaOH}$. <br/>- $\mathrm{NO}_{2}$ brown gas with $\operatorname{con} . \mathrm{H}_{2} \mathrm{SO}_{4}$ <br/>- No reaction with water <br/>Thus, $\mathrm{NH}_{4} \mathrm{NO}_{3}$ can be used to label all three beakers. <br/>(c) $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{CO}_{3}$ will evolve pungent smelling gas $\mathrm{NH}_{3}$ with $\mathrm{NaOH}$ <br/>- Effervescence of $\mathrm{CO}_{2}$ gas with con. $\mathrm{H}_{2} \mathrm{SO}_{4}$ <br/>- No reaction with water. <br/>Thus, $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{CO}_{3}$ can be used to label all three beakers. <br/>Thus, options $(a, c)$ are correct.</div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-does-not-exhibit-optical-isomerism-en-ethylenediamine

which-of-the-following-compounds-does-not-exhibit-optical-isomerism-en-ethylenediamine-74326

<div class="question">Which of the following compounds does not exhibit optical isomerism?<br/>en = ethylenediamine).</div>

['Chemistry', 'Coordination Compounds', 'WBJEE', 'WBJEE 2015']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$\operatorname{cis}-\left[\mathrm{CrCl}_{2}(\mathrm{Ox})_{2}\right]^{3-}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\operatorname{trans}-\left[\mathrm{CrCl}_{2}(\mathrm{ox})_{2}\right]^{3-}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\left[\mathrm{Co}(\mathrm{O} \mathrm{x})(\mathrm{en})_{2}\right]^{+}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answers are: <span class="option-value">$\operatorname{cis}-\left[\mathrm{CrCl}_{2}(\mathrm{Ox})_{2}\right]^{3-}$, $\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}$, $\left[\mathrm{Co}(\mathrm{O} \mathrm{x})(\mathrm{en})_{2}\right]^{+}$</span> </div>

<div class="solution"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2015_che_a77.png"/> <br/> <br/>trans $\left[\mathrm{CrCl}_{2}(\mathrm{ox})_{2}\right]^{3-} \quad$ isomer-optically inactive (superimposable mirror images and plane of symmetry). <br/>$\left.\mathrm{cis}-\mathrm{CrCl}_{2}(\mathrm{ox})_{2}\right]^{3-},\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}$ and $\left[\mathrm{Co}(\mathrm{ox})(\mathrm{en})_{2}\right]^{+}$ <br/>exhibited optical isomerism.</div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-has-maximum-volatility

which-of-the-following-compounds-has-maximum-volatility-46314

<div class="question">Which of the following compounds has maximum volatility?</div>

['Chemistry', 'Chemical Bonding and Molecular Structure', 'WBJEE', 'WBJEE 2011']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/BuFS9CryfWsskygNMQr_tYucxeBZM8EAedqXrdM_YS8.original.fullsize.png"/><br/></span> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/zJORQOPMAR_ABO_9CbQIHPcllZ4JYTr-xKNEf68MhUo.original.fullsize.png"/><br/></span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/EZjQ-3e19y37ObXRH9ZDWuMxPbYnsitDLKFHLdfg7TM.original.fullsize.png"/><br/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/zOMtTUlZ14YPiWAji2YyVfehpVjD6szQRGulpKBn3xs.original.fullsize.png"/><br/></span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/EZjQ-3e19y37ObXRH9ZDWuMxPbYnsitDLKFHLdfg7TM.original.fullsize.png"/><br/></span> </div>

<div class="solution">Hints: Due to intramolecular \(\mathrm{H}\) - bonding</div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-have-magnetic-moment-identical-with-cr-h-2-o-6-3-1

which-of-the-following-compounds-have-magnetic-moment-identical-with-cr-h-2-o-6-3-1-81449

<div class="question">Which of the following compounds have magnetic moment identical with $\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$</div>

['Chemistry', 'Coordination Compounds', 'JEE Main']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\left[\mathrm{Cu}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{4+}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{4+}$</span> </div>

<div class="solution">$\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$ <br/>$\mathrm{Cr} \Rightarrow(\mathrm{Ar}) 3 \mathrm{~d}^{5} 4 \mathrm{~s}^{1}$ <br/>$\mathrm{Cr}^{+3} \Rightarrow(\mathrm{Ar}) 3 \mathrm{~d}^{3} 4 \mathrm{~s}^{0}$ <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/t6aZ3Ag18_5xKD3nj2HikZxX68apAfbwa5o-jXQ42rU.original.fullsize.png"/></div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-have-magnetic-moment-identical-with-cr-h-2-o-6-3

which-of-the-following-compounds-have-magnetic-moment-identical-with-cr-h-2-o-6-3-22630

<div class="question">Which of the following compounds have magnetic moment identical with $\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$</div>

['Chemistry', 'Coordination Compounds', 'WBJEE', 'WBJEE 2021']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\left[\mathrm{Cu}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{4+}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\left[\mathrm{Mn}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{4+}$</span> </div>

<div class="solution">$\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}$ <br/>$\mathrm{Cr} \Rightarrow(\mathrm{Ar}) 3 \mathrm{~d}^{5} 4 \mathrm{~s}^{1}$ <br/>$\mathrm{Cr}^{+3} \Rightarrow(\mathrm{Ar}) 3 \mathrm{~d}^{3} 4 \mathrm{~s}^{0}$ <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/t6aZ3Ag18_5xKD3nj2HikZxX68apAfbwa5o-jXQ42rU.original.fullsize.png"/></div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-is-asymmetric

which-of-the-following-compounds-is-asymmetric-47427

<div class="question">Which of the following compounds is asymmetric?</div>

['Chemistry', 'General Organic Chemistry', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/pXPP4E_8zlt2gMFytD2IRPS0jaHzTkey2EwCXHByfEI.original.fullsize.png"/></span> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/AqCFrbISPWyznG1Vcv-89I9Lf9d69QT0CbzrxBVhvJg.original.fullsize.png"/></span> </li><li class=""> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/zkFpiCjADvN8Oyec9P-fC11QCML53h9BeNRRlZoZ198.original.fullsize.png"/></span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/n-rQVsW0mfrZ8SjLPhwT7wODKnDd1R6mhpt4IGuoM0Y.original.fullsize.png"/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/n-rQVsW0mfrZ8SjLPhwT7wODKnDd1R6mhpt4IGuoM0Y.original.fullsize.png"/></span> </div>

<div class="solution">Hint: No plane of symmetry as well as centre of symmetry is present</div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-is-not-formed-in-iodoform-reaction-of-acetone

which-of-the-following-compounds-is-not-formed-in-iodoform-reaction-of-acetone-52334

<div class="question">Which of the following compounds is not formed in iodoform reaction of acetone</div>

['Chemistry', 'Aldehydes and Ketones', 'WBJEE', 'WBJEE 2011']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{COCH}_2 \mathrm{I}\)</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">\(\mathrm{ICH}_2 \mathrm{COCH}_2 \mathrm{I}\)</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{COCH}_2\)</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{COCI}_3\)</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">\(\mathrm{ICH}_2 \mathrm{COCH}_2 \mathrm{I}\)</span> </div>

<div class="solution">Hints: <img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/DEUZQFqhb_7dT9YdJAdduW78xPyNvHVm7nVfY17Xm18.original.fullsize.png"/><br/></div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-shows-evidence-of-the-strongest-hydrogen-bonding

which-of-the-following-compounds-shows-evidence-of-the-strongest-hydrogen-bonding-49588

<div class="question">Which of the following compounds shows evidence of the strongest hydrogen bonding?</div>

['Chemistry', 'Chemical Bonding and Molecular Structure', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Propan-1-ol</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Propan-2-ol</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Propan-1,2-diol</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">Propan-1,2,3-triol</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Propan-1,2,3-triol</span> </div>

<div class="solution">$$<br/>\text { Hints : Propan-1,2,3 triol have three polar }-\mathrm{OH} \text { group. }<br/>$$</div>

db\MarksBatch2_P4.db

which-of-the-following-compounds-would-not-react-with-lucas-reagent-at-room-temperature

which-of-the-following-compounds-would-not-react-with-lucas-reagent-at-room-temperature-79864

<div class="question">Which of the following compounds would not react with Lucas reagent at room temperature?</div>

['Chemistry', 'Alcohols Phenols and Ethers', 'WBJEE', 'WBJEE 2016']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{H}_{2} \mathrm{C}=\mathrm{CHCH}_{2} \mathrm{OH}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{2} \mathrm{OH}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\left(\mathrm{CH}_{3}\right)_{3} \mathrm{COH}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}$</span> </div>

<div class="solution">Primary ( $1^{\circ}$ )-alcohols do not give Lucas reagent test at room temperature. $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}$ does not undergo $S_{N}1 or S_{N}2$ at room temperature.</div>

db\MarksBatch2_P4.db

which-of-the-following-contributes-to-the-double-helical-structure-of-dna

which-of-the-following-contributes-to-the-double-helical-structure-of-dna-34475

<div class="question">Which of the following contributes to the double helical structure of DNA</div>

['Chemistry', 'Biomolecules', 'WBJEE', 'WBJEE 2009']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">hydrogen bond</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">covalent bond</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">disulphide bond</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">van-der Waal's force</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">hydrogen bond</span> </div>

<div class="solution">No Solution Available</div>

db\MarksBatch2_P4.db

which-of-the-following-diagrams-correctly-shows-the-relation-between-the-terminal-velocity-v-t-of-a-spherical-body-falling-in-a-liquid-and-viscosity-o

which-of-the-following-diagrams-correctly-shows-the-relation-between-the-terminal-velocity-v-t-of-a-spherical-body-falling-in-a-liquid-and-viscosity-o-33936

<div class="question">Which of the following diagrams correctly shows the relation between the terminal velocity $\mathrm{v}_{\mathrm{T}}$ of a spherical body falling in a liquid and viscosity $\eta$ of the liquid?</div>

['Physics', 'Mechanical Properties of Fluids', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/6Rzf58h4_NoTIvnDSvRMKCkxeqJjlTvvXZ8uq4sUOyw.original.fullsize.png"/></span> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2HZN2afSylY13vjwzLWum656_78rSlvwHXlLSNA50gA.original.fullsize.png"/></span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/ZN0zYnjwCPUZdHY40DO5Q-79XpSY4ElhjdP4bOw-kgg.original.fullsize.png"/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/R9ZauFNACnpsBQqW_jVxmkGclplPz4pPLxkzwCsyWls.original.fullsize.png"/></span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/ZN0zYnjwCPUZdHY40DO5Q-79XpSY4ElhjdP4bOw-kgg.original.fullsize.png"/></span> </div>

<div class="solution">Hint : At terminal speed. <br/>$\mathrm{V}_{\mathrm{T}}=\frac{2 \mathrm{r}^{2}}{9 \eta}\left(\rho_{\mathrm{s}}-\rho_{\mathrm{L}}\right) \mathrm{g} \quad$ (Assuming other factor constant) <br/>So, $\mathrm{V}_{\mathrm{T}} \propto \frac{1}{\eta}$ (rectangular hyperbola)</div>

db\MarksBatch2_P4.db

which-of-the-following-does-not-represent-the-mathematical-expression-for-the-heisenberg-uncertainty-principle

which-of-the-following-does-not-represent-the-mathematical-expression-for-the-heisenberg-uncertainty-principle-96668

<div class="question">Which of the following does not represent the mathematical expression for the Heisenberg uncertainty principle?</div>

['Chemistry', 'Structure of Atom', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\Delta x \cdot \Delta P \geq h /(4 \pi)$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\Delta x \cdot \Delta v \geq h /(4 \pi m)$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\Delta E \cdot \Delta t \geq h /(4 \pi)$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\Delta E \cdot \Delta x \geq h /(4 \pi)$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\Delta E \cdot \Delta x \geq h /(4 \pi)$</span> </div>

<div class="solution">From Heisenberg uncertainty principle, $\Delta x \cdot \Delta p \geq \frac{h}{4 \pi}$ <br/>or $\quad \Delta x \cdot m \Delta v \geq \frac{h}{4 \pi}$ <br/>or $\quad \Delta x \cdot \Delta v \geq \frac{h}{4 \pi m}$ <br/>This principle is also applicable for pairs like energy-time $(\Delta E \cdot \Delta t) \quad$ and $\quad$ angular $\begin{array}{llll}\text { moment-angle } &amp; (\Delta w \cdot \Delta \theta) &amp; \text { along } &amp; \text { with }\end{array}$ <br/>position-moment $(\Delta x \cdot \Delta p)$ <br/>Thus, <br/>$$ <br/>\Delta E \cdot \Delta t \geq \frac{h}{4 \pi} <br/>$$</div>

db\MarksBatch2_P4.db

which-of-the-following-electronic-configuration-is-not-possible

which-of-the-following-electronic-configuration-is-not-possible-39930

<div class="question">Which of the following electronic configuration is not possible?</div>

['Chemistry', 'Structure of Atom', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$n=3 l=0 m=0$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$n=3 l=1 m=-1$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$n=2.l=0 \mathrm{mm}-1$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$n=2, l=1 m=0$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$n=2.l=0 \mathrm{mm}-1$</span> </div>

<div class="solution">$n=2,1=0, m=-1$ is not a possible electronie configuration. With $n=2$ and $/-0$, the orbital is having only one $m_{1}$ value i.e. $0 .$ As the value of $m_{1}=-1 t 0+l$ <br/>Other options are correct. <br/><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2018_che_a52.png"/></div>

db\MarksBatch2_P4.db

which-of-the-following-has-the-dimension-if-ml-2-t-2

which-of-the-following-has-the-dimension-if-ml-2-t-2-79705

<div class="question">Which of the following has the dimension if $\left[\mathrm{ML}^{2} \mathrm{T}^{-2}\right] ?$</div>

['Chemistry', 'Thermodynamics (C)', 'WBJEE', 'WBJEE 2017']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Coefficient of viscosity</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">Surface tension</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Vapour pressure</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">Kinetic energy</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Surface tension</span> </div>

<div class="solution">$\because$ Surface tension $(T)=$ Work done per unit area <br/>$$ <br/>\begin{aligned} <br/>\therefore \quad T &amp;=\frac{d W}{d A} \\ <br/>&amp;=\frac{F \cdot d x}{d A} \quad\left(\mathrm{FL}^{-1}=\mathrm{MT}^{-2}\right. <br/>\end{aligned} <br/>$$ <br/>$\therefore$ Dimension of surface tension $=\mathrm{ML}^{2} \mathrm{T}^{-2}$</div>

db\MarksBatch2_P4.db

which-of-the-following-has-the-largest-number-of-atoms

which-of-the-following-has-the-largest-number-of-atoms-91985

<div class="question">Which of the following has the largest number of atoms?</div>

['Chemistry', 'Some Basic Concepts of Chemistry', 'WBJEE', 'WBJEE 2020']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$1 \mathrm{~g}$ of $\mathrm{Ag}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$1 \mathrm{~g}$ of $\mathrm{Fe}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$1 \mathrm{~g}$ of $\mathrm{Cl}_{2}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$1 \mathrm{~g}$ of $\mathrm{Mg}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$1 \mathrm{~g}$ of $\mathrm{Mg}$</span> </div>

<div class="solution">Hint: <br/>Number of atoms of $\mathrm{Ag}=\frac{1}{108} \times \mathrm{N}_{\mathrm{A}}=0.009 \mathrm{~N}_{\mathrm{A}}$ <br/>Number of atoms of $\mathrm{Fe}=\frac{1}{56} \times \mathrm{N}_{\mathrm{A}}=0.0178 \mathrm{~N}_{\mathrm{A}}$ <br/>Number of atoms of $\mathrm{Cl}_{2}=\frac{1}{71} \times 2 \times \mathrm{N}_{\mathrm{A}}=0.028 \mathrm{~N}_{\mathrm{A}}$ <br/>Number of atoms of $\mathrm{Mg}=\frac{1}{24} \mathrm{~N}_{\mathrm{A}}=0.041 \mathrm{~N}_{\mathrm{A}}$ [largest]</div>

db\MarksBatch2_P4.db

which-of-the-following-has-the-strongest-hbond

which-of-the-following-has-the-strongest-hbond-49059

<div class="question">Which of the following has the strongest H-bond?</div>

['Chemistry', 'Chemical Bonding and Molecular Structure', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$0-H-S$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{S}-\mathrm{H}-\mathrm{O}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$F-H$. F</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$F-H-O$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$F-H$. F</span> </div>

<div class="solution">The strongest H-bond is $\mathrm{F}-\mathrm{H}-\mathrm{F}$ because in this case, a hydrogen is bonded to a most. electronegative atom i.e. fluorine. In all other options, hydrogen is bonded to oxygen and sulphur that are less electronegative atom than fluorine. <br/>The correct electronegativity order of elements are as follows: $\mathrm{F}&gt;\mathrm{O}&gt;\mathrm{S}$</div>

db\MarksBatch2_P4.db

which-of-the-following-is-correct-9

which-of-the-following-is-correct-9-68411

<div class="question">Which of the following is correct?</div>

['Chemistry', 'Classification of Elements and Periodicity in Properties', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">Radius of $\mathrm{Ca}^{2+} &lt; \mathrm{Cl}^{-} &lt; \mathrm{S}^{2-}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Radius of $\mathrm{Cl}^{-} &lt; \mathrm{S}^{2-} &lt; \mathrm{Ca}^{2+}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Radius of $\mathrm{S}^{2-}=\mathrm{Cl}^{-}=\mathrm{Ca}^{2+}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">Radius of $\mathrm{S}^{2-} &lt; \mathrm{Cl}^{-} &lt; \mathrm{Ca}^{2+}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Radius of $\mathrm{Ca}^{2+} &lt; \mathrm{Cl}^{-} &lt; \mathrm{S}^{2-}$</span> </div>

<div class="solution">\begin{array}{c|c|c} <br/>\hline Species &amp; Atomic number &amp; Number of electrons \\ <br/>\hline \mathrm{Ca}^{2+} &amp; 20 &amp; 20-2=18 \\ <br/>\mathrm{Cl}^{-} &amp; 17 &amp; 17+1=18 \\ <br/>\mathrm{s}^{2-} &amp; 16 &amp; 16+2=18 \\ <br/>\hline <br/>\end{array} <br/>For isoelectronic species, an increase in atomic number, result in decreased size. Thus, order of radius will be <br/>$$ <br/>\mathrm{Ca}^{2+} &lt; \mathrm{Cl}^{-} &lt; \mathrm{S}^{2-} <br/>$$</div>

db\MarksBatch2_P4.db

which-of-the-following-is-correct-10

which-of-the-following-is-correct-10-53000

<div class="question">Which of the following is correct?</div>

['Chemistry', 'Thermodynamics (C)', 'WBJEE', 'WBJEE 2012']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">Evaporation of water causes an increase in disorder of the system</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Melting of ice causes a decrease in randomness of the system</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Condensation of steam causes an increase in disorder of the system</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">There is practically no change in the randomness of the system when water is evaporated</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Evaporation of water causes an increase in disorder of the system</span> </div>

<div class="solution">Water evaporates into steam. In this physical state its disorder or randomness increases.</div>

db\MarksBatch2_P4.db

which-of-the-following-is-least-thermally-stable

which-of-the-following-is-least-thermally-stable-10294

<div class="question">Which of the following is least thermally stable?</div>

['Chemistry', 'Practical Chemistry', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{MgCO}_{3}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{CaCO}_{3}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{SrCO}_{3}$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\mathrm{BeCO}_{3}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{BeCO}_{3}$</span> </div>

<div class="solution">BeCO, is least thermally stable. The thermal stability of carbonates increases down the group <br/>i.e from Be to Ba. $\mathrm{BeCO}_{3} &lt; \mathrm{MgCO}_{3} &lt; \mathrm{CaCO}_{3} &lt; \mathrm{SrCO}_{3} &lt; \mathrm{BaCO}_{3}$ <br/>$(523 \mathrm{K}) \quad(813 \mathrm{K})$ <br/>$(1173 \mathrm{K}) \quad(1562 \mathrm{K}) \quad(1633 \mathrm{K})$ <br/>BeCO, is unstable to the extent that it is stable only in atmosphere of $\mathrm{CO}_{y}$. These carbonates show reversible decomposition in closed container. <br/>$M \mathrm{CO}, \quad \rightarrow \mathrm{MO}+\mathrm{CO}_{2}$ <br/>More stable the oxide is formed, lesser will be stability of carbonates.</div>

db\MarksBatch2_P4.db

which-of-the-following-is-not-always-true

which-of-the-following-is-not-always-true-55951

<div class="question">Which of the following is not always true?</div>

['Mathematics', 'Vector Algebra', 'WBJEE', 'WBJEE 2015']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mid a+b\mid^{2}=|a|^2+|b|^2. \text{if a and b are perpendicular to each other}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mid a+\lambda b| \geq|a|$ for all $\lambda \in R$ if a and b are perpendicular to each other</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mid a+b \mid^{2}+\mid a-b \mid^{2}=2(|a|^2+|b|^2)$</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">$\mid a+\lambda b| \geq|a|$ for all $\lambda \in R$ if a is parallel to b</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mid a+\lambda b| \geq|a|$ for all $\lambda \in R$ if a is parallel to b</span> </div>

<div class="solution">(a) If a and b are perpendicular to each other, then<br/>$\mathbf{a} \cdot \mathbf{b}=0$<br/>Now consider,<br/>$\begin{aligned}<br/>|\mathbf{a}+\mathbf{b}|^{2} &amp;=(\mathbf{a}+\mathbf{b}) \cdot(\mathbf{a}+\mathbf{b}) \\<br/>&amp;=|\mathbf{a}|^{2}+|\mathbf{b}|^{2}<br/>\end{aligned}$<br/>So, option (a) is always true.<br/>(b) If $\mathbf{a}$ and $\mathbf{b}$ are perpendicular to each other, then<br/>$\mathbf{a} \cdot \mathbf{b}=0$<br/>Now consider, $\begin{aligned}|\mathbf{a}+\lambda \mathbf{b}|^{2} &amp;=(\mathbf{a}+\lambda \mathbf{b}) \cdot(\mathbf{a}+\lambda \mathbf{b}) \\ &amp;=|\mathbf{a}|^{2}+\lambda^{2}|\mathbf{b}|^{2} \\ \Rightarrow|\mathbf{a}+\lambda \mathbf{b}| &amp;=\sqrt{|\mathbf{a}|^{2}+\lambda^{2}|\mathbf{b}|^{2}} \end{aligned}$<br/>$\geq|\mathbf{a}|$ for all $\lambda \in R$<br/>So, option (b) is always true.<br/>(c) Consider,<br/>$\left|a+\left.b\right|^{2}+|a-b|^{2}=(a+b) \cdot(a+b) + (a-b) \cdot (a-b)\right.$<br/>$=|\mathbf{a}|^{2}+\mathbf{a} \cdot \mathbf{b}+\mathbf{b} \cdot \mathbf{a}+|\mathbf{b}|^{2}+|\mathbf{a}|^{2}-\mathbf{a} \cdot \mathbf{b} -b \cdot a + |b|^2$<br/>$=2\left(|\mathbf{a}|^{2}+|\mathbf{b}|^{2}\right)$<br/>So, option (c) is always true.<br/>(d) Consider.<br/>$\mathbf{a}=-\mathbf{b} \text { and } \mathbf{b} \neq 0$<br/>Then, $|\mathbf{a}+\lambda \mathbf{b}| \geq|\mathbf{a}|$<br/>$\Rightarrow|-\mathbf{b}+\lambda \mathbf{b}| \geq|-\mathbf{b}|$<br/>$\Rightarrow \quad|\mathbf{b}||\lambda-1| \geq|\mathbf{b}| \Rightarrow|\lambda-1| \geq 1$<br/>which is not true for all $\lambda,$ as we consider $\lambda=\frac{1}{2}$, then it is not true<br/>Hence, option (d) is not always true.</div>

db\MarksBatch2_P4.db

which-of-the-following-is-present-in-maximum-amount-in-acid-rain-1

which-of-the-following-is-present-in-maximum-amount-in-acid-rain-1-97473

<div class="question">Which of the following is present in maximum amount in 'acid rain'?</div>

['Chemistry', 'Environmental Chemistry', 'WBJEE', 'WBJEE 2018']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{HNO}_{3}$</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">$\mathrm{H}_{2} \mathrm{SO}_{4}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">C</span> <span class="option-data">HCI</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\mathrm{H}_{2} \mathrm{CO}_{3}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{H}_{2} \mathrm{SO}_{4}$</span> </div>

<div class="solution">$\mathrm{H}_{2} \mathrm{SO}_{4}$ (sulphuric acid) is present in maximu $\mathrm{h}_{4}$ amount in 'acid rain'. Oxides of nitrogen and sulphur, released into the atmosphere from industries and automobiles thermal power plants, are the miain sources of acid rain. These oxides on oxidation followed by hydrolysis give sulphuric acid and nitric acid that alongwith $\mathrm{HCl}$ are responsible for the acidity of rain. The oxidation reaction is catalysed by particulate matter present in the polluted atmosphere. $2 \mathrm{SO}_{2}(g)+\mathrm{O}_{2}(g)+2 \mathrm{H}, \mathrm{O}(l) \longrightarrow 2 \mathrm{H}_{2} \mathrm{SO}_{4}(a q)$ <br/>$4 \mathrm{NO}_{2}(g)+\mathrm{O}_{2}(g)+2 \mathrm{H}_{2} \mathrm{O}\left(h \longrightarrow 4 \mathrm{HNO}_{3}(a q)\right.$</div>

db\MarksBatch2_P4.db

which-of-the-following-is-radioactive

which-of-the-following-is-radioactive-52333

<div class="question">Which of the following is radioactive?</div>

['Chemistry', 'Hydrogen', 'WBJEE', 'WBJEE 2022']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Hydrogen</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Deuterium</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">Tritium</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">none</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Tritium</span> </div>

<div class="solution">Fact</div>

db\MarksBatch2_P4.db

which-of-the-following-is-used-to-prepare-mathrmcl2-gas-at-room-temperature-from-concentrated-mathrmhcl

which-of-the-following-is-used-to-prepare-mathrmcl2-gas-at-room-temperature-from-concentrated-mathrmhcl-27797

<div class="question">Which of the following is used to prepare \(\mathrm{Cl}_2\) gas at room temperature from concentrated \(\mathrm{HCl}\) ?</div>

['Chemistry', 'p Block Elements (Group 15, 16, 17 & 18)', 'WBJEE', 'WBJEE 2011']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">\(\mathrm{MnO}_2\)</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">\(\mathrm{H}_2 \mathrm{~S}\)</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">\(\mathrm{KMnO}_4\)</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">\(\mathrm{Cr}_2 \mathrm{O}_3\)</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">\(\mathrm{KMnO}_4\)</span> </div>

<div class="solution">Hints : \(2 \mathrm{MnO}_4^{-}+16 \mathrm{H}^{+}+10 \mathrm{Cl}^{-} \rightarrow 2 \mathrm{Mn}^{2+}+5 \mathrm{Cl}_2+8 \mathrm{H}_2 \mathrm{O}\)</div>

db\MarksBatch2_P4.db

which-of-the-following-isare-always-false

which-of-the-following-isare-always-false-84175

<div class="question">Which of the following is/are always false?</div>

['Mathematics', 'Quadratic Equation', 'WBJEE', 'WBJEE 2015']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">A quadratic equation with rational coefficients hes zero or two irrational roots</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">A quadratic equation with real coefficients has zero or two non-real roots</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">A quadratic equation with irrational coeflicients has zero or two irrational roots</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">A quadratic equation with integer coefficients has zero or two irrational roots</span> </li> </ul>

<div class="correct-answer"> The correct answers are: <span class="option-value">A quadratic equation with irrational coeflicients has zero or two irrational roots</span> </div>

<div class="solution">If a quadratic equation has irrational coefficients, then roots are also inational. <br/>So, option (c) is always false.</div>

db\MarksBatch2_P4.db

which-of-the-following-materials-is-the-best-conductor-of-electricity

which-of-the-following-materials-is-the-best-conductor-of-electricity-71446

<div class="question">Which of the following materials is the best conductor of electricity?</div>

['Physics', 'Semiconductors', 'WBJEE', 'WBJEE 2009']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">Platinum</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Gold</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Silicon</span> </li><li class="correct"> <span class="option-label">D</span> <span class="option-data">Copper</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Copper</span> </div>

<div class="solution">No Solution Available</div>

db\MarksBatch2_P4.db

which-of-the-following-metals-has-the-largest-abundance-in-the-earths-crust

which-of-the-following-metals-has-the-largest-abundance-in-the-earths-crust-72106

<div class="question">Which of the following metals has the largest abundance in the earth's crust ?</div>

['Chemistry', 'General Principles and Processes of Isolation of Metals', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">Aluminium</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">Calcium</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">Magnesium</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">Sodium</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">Aluminium</span> </div>

<div class="solution">No Solution Available</div>

db\MarksBatch2_P4.db

which-of-the-following-mixtures-acts-as-buffer-solution

which-of-the-following-mixtures-acts-as-buffer-solution-62595

<div class="question">Which of the following mixtures act(s) as buffer solution?</div>

['Chemistry', 'Ionic Equilibrium', 'WBJEE', 'WBJEE 2023']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">\(\mathrm{NaOH}+\mathrm{CH}_3 \mathrm{COOH}\) (1:1 mole ratio)</span> </li><li class="correct"> <span class="option-label">B</span> <span class="option-data">\(\mathrm{NH}_4 \mathrm{OH}+\mathrm{HCl}(2: 1\) mole ratio)</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{COOH}+\mathrm{NaOH}(2: 1\) more ratio)</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">\(\mathrm{CH}_3 \mathrm{COOH}+\mathrm{NaOH}(1: 2\) mole ratio)</span> </li> </ul>

<div class="correct-answer"> The correct answers are: <span class="option-value">\(\mathrm{NH}_4 \mathrm{OH}+\mathrm{HCl}(2: 1\) mole ratio), \(\mathrm{CH}_3 \mathrm{COOH}+\mathrm{NaOH}(2: 1\) more ratio)</span> </div>

<div class="solution">Hint : (B) \(\mathrm{NH}_4 \mathrm{OH}+\mathrm{HCl}~(2: 1 \text { mole ratio}) \rightarrow \underset{\large 1 \quad:\quad 1 \atop <br/>\large \text{Buffer} \quad \text{buffer}}{\mathrm{NH}_4 \mathrm{Cl}+\mathrm{NH}_4 \mathrm{OH}}\)<br/>(C) \(\mathrm{CH}_3 \mathrm{COOH}+\mathrm{NaOH}(2: 1\) mole ratio \() \rightarrow \underset{\large 1\quad : \quad 1 \atop \large \text{Acidic buffer}}{\mathrm{CH}_3 \mathrm{COONa}+\mathrm{CH}_3 \mathrm{COOH}}\)</div>

db\MarksBatch2_P4.db

which-of-the-following-mixtures-will-have-the-lowest-ph-at-298-k

which-of-the-following-mixtures-will-have-the-lowest-ph-at-298-k-71327

<div class="question">Which of the following mixtures will have the lowest pH at 298 K?</div>

['Chemistry', 'Ionic Equilibrium', 'WBJEE', 'WBJEE 2019']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$10 \mathrm{mL}$ 0.05 $\mathrm{N}$ $\mathrm{CH}_{3} \mathrm{COOH}+5 \mathrm{mL}$ 0.1 $\mathrm{N}$ $\mathrm{NH}_{4} \mathrm{OH}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$5 \mathrm{mL}$ 0.2 $\mathrm{N}$ $\mathrm{NH}_{4} \mathrm{Cl}+5 \mathrm{mL}$. $0.2 \mathrm{N }$ $\mathrm{NH}_{4} \mathrm{OH}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$5 \mathrm{mL}$. $0.1 \mathrm{N}$ $\mathrm{CH}_{5} \mathrm{COOH}+10 \mathrm{mL}$ 0.05 $\mathrm{N}$ $\mathrm{CH}_{3} \mathrm{COONa}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$5 \mathrm{mL}$ 0.1 $\mathrm{N}$ $\mathrm{CH}_{3} \mathrm{COOH}+5 \mathrm{mL}$ 0.1 $\mathrm{N}$ $\mathrm{NaOH}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$5 \mathrm{mL}$. $0.1 \mathrm{N}$ $\mathrm{CH}_{5} \mathrm{COOH}+10 \mathrm{mL}$ 0.05 $\mathrm{N}$ $\mathrm{CH}_{3} \mathrm{COONa}$</span> </div>

<div class="solution">Key Point For buffer solutions, <br/>$$ <br/>\mathrm{pH}=\mathrm{pK}_{a}+\log \frac{[\text { Salt }]}{[\text { Acid }] /[\text { Base }]} <br/>$$ <br/>Moles of $\mathrm{CH}_{3} \mathrm{COOH}=5 \mathrm{mL} \times 0.01 \mathrm{m} \mathrm{mol}=0.5 \mathrm{m} \mathrm{mol}$ <br/>Moles of $\mathrm{CH}_{3} \mathrm{COONa}=10 \mathrm{mL} \times 0.05 \mathrm{m} \mathrm{mol}$ <br/>$$ <br/>=0.5 \mathrm{m} \mathrm{mol} <br/>$$ <br/>Total volume of solution $=5+10=15 \mathrm{mL}$ <br/>$$ <br/>\therefore \quad \mathrm{pH}=\mathrm{p} K_{a}+\log \frac{0.5 / 15}{0.5 / 15} \Rightarrow \mathrm{pH}=\mathrm{p} K_{a} <br/>$$ <br/>The value of $\mathrm{p} K_{a}$ is the lowest for the mixture of $\begin{array}{llll}\mathrm{CH}_{3} \mathrm{COOH} &amp; \text { and } \mathrm{CH}_{3} \mathrm{COONa} &amp; \text { (acidic buffer). }\end{array}$ <br/>Therefore, it has lowest pH. Hence, pH value for option (c) is the lowest.</div>

db\MarksBatch2_P4.db

which-of-the-following-orbitals-will-have-zero-probability-of-finding-the-electron-in-the-yz-plane

which-of-the-following-orbitals-will-have-zero-probability-of-finding-the-electron-in-the-yz-plane-27669

<div class="question">Which of the following orbitals will have zero probability of finding the electron in the yz plane ?</div>

['Chemistry', 'Structure of Atom', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data">$P_x$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{P}_{\mathrm{y}}$</span> </li><li class=""> <span class="option-label">C</span> <span class="option-data">$\mathrm{P}_{\mathrm{z}}$</span> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\mathrm{d}_{\mathrm{yz}}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$P_x$</span> </div>

<div class="solution">Hints : $P_x$ orbital lies along $x$-axis only.</div>

db\MarksBatch2_P4.db

which-of-the-following-orders-regarding-ionization-energy-is-correct

which-of-the-following-orders-regarding-ionization-energy-is-correct-76504

<div class="question">Which of the following orders regarding ionization energy is correct?</div>

['Chemistry', 'Classification of Elements and Periodicity in Properties', 'WBJEE', 'WBJEE 2010']

<ul class="options"> <li class=""> <span class="option-label">A</span> <span class="option-data">$\mathrm{N}&gt;\mathrm{O}&gt;\mathrm{F}$</span> </li><li class=""> <span class="option-label">B</span> <span class="option-data">$\mathrm{N} &lt; \mathrm{O} &lt; \mathrm{F}$</span> </li><li class="correct"> <span class="option-label">C</span> <span class="option-data">$\mathrm{N}&gt;\mathrm{O} &lt; \mathrm{F}$</span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">D</span> <span class="option-data">$\mathrm{N} &lt; \mathrm{O}&gt;\mathrm{F}$</span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value">$\mathrm{N}&gt;\mathrm{O} &lt; \mathrm{F}$</span> </div>

<div class="solution">Hints : As IE $1 \mathrm{~N}&gt;\mathrm{O}$ (because of half filled orbitals of $\mathrm{N}$ ) and $\mathrm{O} &lt; \mathrm{F}$ (because of smaller size of $\mathrm{F}$ )</div>

db\MarksBatch2_P4.db

which-of-the-following-plots-represent-an-exothermic-reaction-1

which-of-the-following-plots-represent-an-exothermic-reaction-1-90711

<div class="question">Which of the following plots represent an exothermic reaction?</div>

['Chemistry', 'Chemical Equilibrium', 'JEE Main']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_opta.png"/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_optb.png"/></span> </li><li class=""> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_optc.png"/></span> </li><li class=""> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_optd.png"/></span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_opta.png"/></span> </div>

<div class="solution">For exothermic reaction. <br/>$\because$ <br/>$K_{p} \propto \frac{1}{T}$ <br/>Thus, as $\frac{1}{T}$ increases (i.e. $T$ decreases), $K_{p}$ increases. <br/>$\because$ $\Delta$ H for exothermic reactions is negative.</div>

db\MarksBatch2_P4.db

which-of-the-following-plots-represent-an-exothermic-reaction

which-of-the-following-plots-represent-an-exothermic-reaction-56745

<div class="question">Which of the following plots represent an exothermic reaction?</div>

['Chemistry', 'Chemical Equilibrium', 'WBJEE', 'WBJEE 2016']

<ul class="options"> <li class="correct"> <span class="option-label">A</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_opta.png"/></span> <svg fill="none" height="24" viewbox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg"> <path d="M12 2.25C10.0716 2.25 8.18657 2.82183 6.58319 3.89317C4.97982 4.96452 3.73013 6.48726 2.99218 8.26884C2.25422 10.0504 2.06114 12.0108 2.43735 13.9021C2.81355 15.7934 3.74215 17.5307 5.10571 18.8943C6.46928 20.2579 8.20656 21.1865 10.0979 21.5627C11.9892 21.9389 13.9496 21.7458 15.7312 21.0078C17.5127 20.2699 19.0355 19.0202 20.1068 17.4168C21.1782 15.8134 21.75 13.9284 21.75 12C21.7473 9.41498 20.7192 6.93661 18.8913 5.10872C17.0634 3.28084 14.585 2.25273 12 2.25ZM16.2806 10.2806L11.0306 15.5306C10.961 15.6004 10.8783 15.6557 10.7872 15.6934C10.6962 15.7312 10.5986 15.7506 10.5 15.7506C10.4014 15.7506 10.3038 15.7312 10.2128 15.6934C10.1218 15.6557 10.039 15.6004 9.96938 15.5306L7.71938 13.2806C7.57865 13.1399 7.49959 12.949 7.49959 12.75C7.49959 12.551 7.57865 12.3601 7.71938 12.2194C7.86011 12.0786 8.05098 11.9996 8.25 11.9996C8.44903 11.9996 8.6399 12.0786 8.78063 12.2194L10.5 13.9397L15.2194 9.21937C15.2891 9.14969 15.3718 9.09442 15.4628 9.0567C15.5539 9.01899 15.6515 8.99958 15.75 8.99958C15.8486 8.99958 15.9461 9.01899 16.0372 9.0567C16.1282 9.09442 16.2109 9.14969 16.2806 9.21937C16.3503 9.28906 16.4056 9.37178 16.4433 9.46283C16.481 9.55387 16.5004 9.65145 16.5004 9.75C16.5004 9.84855 16.481 9.94613 16.4433 10.0372C16.4056 10.1282 16.3503 10.2109 16.2806 10.2806Z" fill="#24A865"></path> </svg> </li><li class=""> <span class="option-label">B</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_optb.png"/></span> </li><li class=""> <span class="option-label">C</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_optc.png"/></span> </li><li class=""> <span class="option-label">D</span> <span class="option-data"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_optd.png"/></span> </li> </ul>

<div class="correct-answer"> The correct answer is: <span class="option-value"><img src="https://cdn-question-pool.getmarks.app/pyq/wbjee/2016_che_q23_opta.png"/></span> </div>

<div class="solution">For exothermic reaction. <br/>$\because$ <br/>$K_{p} \propto \frac{1}{T}$ <br/>Thus, as $\frac{1}{T}$ increases (i.e. $T$ decreases), $K_{p}$ increases. <br/>$\because$ $\Delta$ H for exothermic reactions is negative.</div>

db\MarksBatch2_P4.db