NEET UG 2004 — Chemistry Physical Chemistry

2004mcqhard

The standard e.m.f of a galvanic cell involving cell reaction with $\mathrm{n}=2$ is found to be $0.295 \mathrm{~V}$ at $25^{\circ} \mathrm{C}$ . The equilibrium constant of the reaction would be: (Given $\mathrm{F}=96500 \mathrm{C} \mathrm{mol}^{-1}, \mathrm{R}=8.314 \mathrm{~J}$ $\mathrm{K}^{-1} \mathrm{~mol}^{-1}$

Official previous-year question

Held on 30 Apr 2004 · Verified 9 Jul 2026.

Options

A
$2.0 \times 10^{11}$
B
$4.0 \times 10^{12}$
C
$1.0 \times 10^2$
D
$1.0 \times 10^{10}$

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Solution

$\mathrm{E}=\mathrm{E}^{\circ}-\frac{0.0591}{n} \log _{10} \mathrm{Q}$ at $25^{\circ} \mathrm{C}$ At equilibrium, $\mathrm{E}=0, \mathrm{Q}=\mathrm{K}$ $0=\mathrm{E}^{\circ}-\frac{0.0591}{n} \log _{10} \mathrm{~K}$ or, $\mathrm{K}=$ Antilog $\left[\frac{n \mathrm{E}^{\circ}}{0.0591}\right]$ or, $\mathrm{K}=$ Antilog $\left[\frac{2 \times 0.295}{0.0591}\right]$ $\begin{aligned} & =\text { Antilog }\left[\frac{0.590}{0.0591}\right] \\ & =\text { Antilog } 10=1 \times 10^{10} . \end{aligned}$ Related Theory The cell potential is the difference between the electrode potentials (reduction potentials) of the cathode and anode. It is called the standard electromotive force (emf) of the cell when no current is drawn through the cells.

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NEET UG 2004 — Chemistry Physical Chemistry

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NEET UG 2004 — Chemistry Physical Chemistry

Options

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Solution

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NEET UG Physical Chemistry in other years

More NEET UG Physical Chemistry questions

Other Chemistry topics for NEET UG

Organic Chemistry

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