A variable, the opposite external potential $\left({\mathrm{E}}_{\mathrm{ext}}\right)$ is applied to the cell $\mathrm{Z}\mathrm{n}\mathrm{ }|\mathrm{ }\mathrm{Z}{\mathrm{n}}^{2+}\mathrm{ }\left(1\mathrm{M}\right)\parallel \mathrm{C}{\mathrm{u}}^{2+}\mathrm{ }\left(1\mathrm{ }\mathrm{M}\right)|\mathrm{}\mathrm{}\mathrm{C}\mathrm{u}$, of potential $1.1 \mathrm{V}$. When ${\mathrm{E}}_{\mathrm{e}\mathrm{x}\mathrm{t}}<1.1\mathrm{ }\mathrm{V}$ and ${\mathrm{E}}_{\mathrm{e}\mathrm{x}\mathrm{t}}>1.1\mathrm{ }\mathrm{V}$, respectively electrons flow from

The cell potential for the following cell $\mathrm{Pt}\left|{\mathrm{H}}_2\left(\mathrm{g}\right)\right|{\mathrm{H}}^{+}\left(\mathrm{aq}\right)\left|\right|\left.{\mathrm{Cu}}^{2+}\left(0.01\mathrm{M}\right)\right|\mathrm{Cu}\left(\mathrm{s}\right)$ is $0.576 \mathrm{V}$ at $298 \mathrm{K}$. The $\mathrm{pH}$ of the solution is (Nearest integer)

(Given : ${\mathrm{E}}_{{\mathrm{Cu}}^{2+}/\mathrm{Cu}}^{\mathrm{o}}=0.34 \mathrm{V}$ and $\frac{2.303\mathrm{RT}}{\mathrm{F}}=0.06 \mathrm{V}$)

In a cell, the following reactions take place

${\mathrm{Fe}}^{2+}\to {\mathrm{Fe}}^{3+}+{\mathrm{e}}^{-} {{\mathrm{E}}^{\mathrm{o}}}_{{\mathrm{Fe}}^{3+}/{\mathrm{Fe}}^{2+}}=0.77 \mathrm{V}$

$2{\mathrm{I}}^{-}\to {\mathrm{I}}_2+2{\mathrm{e}}^{-} {\mathrm{E}}_{{\mathrm{I}}_2/{\mathrm{I}}^{-}}^0=0.54 \mathrm{V}$

The standard electrode potential for the spontaneous reaction in the cell is $\mathrm{x}\times {10}^{-2} \mathrm{V} \mathrm{at} 298 \mathrm{K}$. The value of $\mathrm{x}$ is - (Nearest Integer)

The correct order of reduction potentials of the following pairs is

A. ${\mathrm{Cl}}_2/{\mathrm{Cl}}^{-}$

B. ${\mathrm{I}}_2/{\mathrm{I}}^{-}$

C. ${\mathrm{Ag}}^{+}/\mathrm{Ag}$

D. ${\mathrm{Na}}^{+}/\mathrm{Na}$

E. ${\mathrm{Li}}^{+}/\mathrm{Li}$

Choose the correct answer from the options given below.

A solution of ${\mathrm{Fe}}_2{\left({\mathrm{SO}}_4\right)}_3$ is electrolyzed for '$\mathrm{x}$' min with a current of $1.5 \mathrm{A}$ to deposit $0.3482 \mathrm{g}$ of $\mathrm{Fe}$. The value of $\mathrm{x}$ is - [nearest integer]

Given : $1 \mathrm{F}=96500 {\mathrm{Cmol}}^{-1}$. Atomic mass of $\mathrm{Fe}=56 {\mathrm{gmol}}^{-1}$

$\mathrm{Cu}\left(\mathrm{s}\right)+{\mathrm{Sn}}^{2+}\left(0.001\mathrm{M}\right)\to {\mathrm{Cu}}^{2+}\left(0.01\mathrm{M}\right)+\mathrm{Sn}\left(\mathrm{s}\right)$

The Gibbs free energy change for the above reaction at $298 \mathrm{K}$ is $x\times {10}^{-1} \mathrm{kJ}{ \mathrm{mol}}^{-1}$. The value of $\mathrm{x}$ is____[nearest integer]

[Given : ${\mathrm{E}}_{{\mathrm{Cu}}^{2+}/\mathrm{Cu}}^{\ominus }=0.34 \mathrm{V};{\mathrm{E}}_{{\mathrm{Sn}}^{2+}/\mathrm{Sn}}^{\ominus }=-0.14 \mathrm{V};\mathrm{F}=96500{\mathrm{Cmol}}^{-1}$]

The ${\left(\frac{\partial \mathrm{E}}{\partial \mathrm{T}}\right)}_{\mathrm{P}}$ of different types of half cells are as follows :
$\begin{array}{cccc}\mathrm{A}& \mathrm{B}& \mathrm{C}& \mathrm{D}\\ 1\times {10}^{-4}& 2\times {10}^{-4}& 0.1\times {10}^{-4}& 0.2\times {10}^{-4}\end{array}$

(Where $\mathrm{E}$ is the electromotive force). Which of the above half cells would be preferred to be used as reference electrode