Electro chemistry practice · Mixed difficulty

Assertion: Copper sulphate solution cannot be stored in iron-vessel.

Reason: Copper atoms are oxidized by iron ions.

A solution of $\mathrm{CuSO}_4$ is electrolyzed for 7 minutes with a current of $0.6 \mathrm{~A}$. The amount of electricity passed is equal to:

The equivalent conductivity of a solution containing 2.54 g of $\mathrm{CuS}{\mathrm{O}_4}{\kern 1pt} {\kern 1pt} \mathrm{per L is}{\kern 1pt} {\kern 1pt} {\kern 1pt} 91.0{\mathrm{\Omega }^{ - 1}}\mathrm{c}{\mathrm{m}^2}\mathrm{e}{\mathrm{q}^{ - 1}}$. Its conductivity would be

Given, $E_{C{l_2}/C{l^ - }}^\mathrm{o} = 1.36\,V,\,E_{C{r^{3 + }}/Cr}^\mathrm{o} = - 0.74\,V$
$E_{C{r_2}O_7^{2 - }/C{r^{3 + }}}^\mathrm{o} = 1.33\,V,\,E_{MnO_4^ - /M{n^{2 + }}}^\mathrm{o} = 1.51\,V$
Among the following, the strongest reducing agent is

Select the correct statement(s) for the weak electrolyte.

An object whose surface area is $80 \mathrm{~cm}^2$ is to be plated with an even layer of gold $8.0 \times 10^{-4} \mathrm{~cm}$ thick. The density of gold is $19.7 \mathrm{~g} / \mathrm{cm}^3.$ The object is placed in a solution of $\mathrm{Au}\left(\mathrm{NO}_3\right)_3$ and a current of $\text{2.4 A}$ is applied. The time required for the electroplating to be completed, assuming that the layer of gold builds up evenly, is $(\mathrm{Au}=197)$

The sum of the two transport number of ions for an electrolyte is always equal to :

${E^ \circ }$ values of $M{g^{(2 + )}}$ / Mg is -2.37 V, of $\mathrm{Z}{\mathrm{n}^{2 + }}$ / Zn is -0.76 V and $\mathrm{F}{\mathrm{e}^{2 + }}$ / Fe is -0.44 V.
Which of the statements is correct?

Hydrogen gas is not liberated when the following metal is added to dil. HCl

Following cell has EMF $0.7995 \mathrm{~V}$.

$\mathrm{Pt}\left|\mathrm{H}_2(1 \mathrm{~atm})\right| \mathrm{HNO}_3(1 \mathrm{M}) \| \mathrm{AgNO}_3(1 \mathrm{M}) \mid \mathrm{Ag}$

If we add enough $\mathrm{KCl}$ to the $\mathrm{Ag}$ cell so that the
final $\mathrm{Cl}^{-}$is $1 \mathrm{M}$. Now the measured emf of the cell is $0.222 \mathrm{~V}$. The $\mathrm{K}_{s p}$ of $\mathrm{AgCl}$ would be-

The quantity of charge required to obtain one mole of aluminium from $A{l_2}{O_3}$ is

For given cell, $\mathrm{Mg} / \mathrm{Mg}^{2+}(0.01 \mathrm{M}) \| \mathrm{Ag}^{+}(0.01 \mathrm{M}) / \mathrm{Ag}$, if $\mathrm{E}_{\text {cel }}^{\circ}=3.17 \mathrm{~V}$, then $\mathrm{E}_{\text {cell }}$ will be

Two electrolytic cells one containing acidified ferrous chloride and another acidified ferric chloride are connected in series. The ratio of iron deposited at cathodes in the two cells when electricity is passed through the cells will be

A certain current liberates 0.504 g of hydrogen in 2 hr. How many gram of copper can be liberated by the same current flowing for the same time in $\mathrm{CuS}{\mathrm{O}_4}$ solution?

Which process occurs in the electrolysis of aqueous solution of nickel chloride at nickel anode?

${\mathrm{I}_2}\left( s \right)|{\mathrm{I}^ - }\left( {0.1\mathrm{M}} \right)$ half-cell is connected to a ${\mathrm{H}^ + }\left( {aq} \right)\left| {{\mathrm{H}_2}\left( {1\mathrm{bar}} \right)} \right|$ Pt half-cell and emf is found to be 0.7714 V. If $E_{{I^2}/{I^ - }}^ \circ = 0.535\mathrm{V}$, find the $\mathrm{pH}$ of ${\mathrm{H}^ + }/{\mathrm{H}_2}$ half-cell

Statement I: on dilution of the solution the electrode potential increases

Statement II: Effect of dilution on electrode potential depends on electrode whether it is metal or non-metal

Give the products available on the cathode and the anode respectively during the electrolysis of an aqueous solution of $\mathrm{MgS}{\mathrm{O}_4}$ between inert electrodes.

$\mathrm{MnO}_4^ - + 8{\mathrm{H}^ + } + 5{e^ - } \to \mathrm{M}{\mathrm{n}^{2 + }} + 4{\mathrm{H}_2}\mathrm{O};{E^ \circ } = 1.51\mathrm{V}$

$\mathrm{Mn}{\mathrm{O}_4} + 4{\mathrm{H}^ + } + 2{e^ - } \to \mathrm{M}{\mathrm{n}^{2 + }} + 2{\mathrm{H}_2}\mathrm{O};{E^ \circ } = 1.23\mathrm{V}$

$E_{\mathrm{MnO}_4^ - |\mathrm{Mn}{\mathrm{O}_2}}^ \circ$ is

The amount of electricity required to liberate 1 g-equiv of Cu is

Consider the following cell

$\mathrm{Pt}\left|\mathrm{H}_2(\mathrm{g})\right| \mathrm{HCl}(\mathrm{aq}) \| \mathrm{Cl}^{-}(\mathrm{aq})|\mathrm{AgCl}(\mathrm{s})| \mathrm{Ag}(\mathrm{s})$

E.M.F of the above cell is 0.355 V at $25^{\circ} \mathrm{C}$ and 0.305 V at $30^{\circ} \mathrm{C}.$ The enthalpy change per mole of the reaction taking place at $25^{\circ} \mathrm{C}$ is

[Consider 1 mole of Ag is formed]

Assertion (A): In weak electrolytes, the change in $\Lambda_{\mathrm{m}}$ with dilution is mainly due to increase in degree of dissociation
Reason (R): At a given concentration of weak electrolyte the degree of dissociation $\alpha=\frac{\Lambda_{\mathrm{m}}^0}{\Lambda_{\mathrm{m}}}$

Assertion : For cell reaction; at $298 \mathrm{KZn}(\mathrm{s})+\mathrm{Cu}^{+2}(1 \mathrm{M}) \rightleftharpoons \mathrm{Zn}^{+2}(1 \mathrm{M})+\mathrm{Cu}(\mathrm{s})$ $\mathrm{E}_{\text {cell }}^{\circ}=0$

Reason: At standard condition ; cell potential is always zero.

At infinite dilution stage, the solution of $\mathrm{C}{\mathrm{H}_3}\mathrm{COOH}$ in water does not contain :

Assertion: Sodium ions are discharged at the $\mathrm{Hg}$ electrode during electrolysis in preference to $\mathrm{H}^{+}$ions.

Reason: The nature of electrode also affects the order of discharge of cations.

The conductivity of a $0.1N{\kern 1pt} \mathrm{KCl}$ solution at 230C is 0.012 $\mathrm{oh}{\mathrm{m}^{ - 1}}{\kern 1pt}{\kern 1pt}\mathrm{c}{\mathrm{m}^{ - 1}}$ .The resistance of the cell containing the solution at the same temperature was found to be 55 ohm. The cell constant will be :

Calculate equilibrium constant (approx) at $25^{\circ} \mathrm{C}$ for the cell reaction

$\mathrm{Fe}_{(\mathrm{s})}+\mathrm{CuSO}_4 \rightleftharpoons \mathrm{FeSO}_4+\mathrm{Cu}_{(\mathrm{s})}$
Given $\begin{aligned} & \mathrm{E}_{\mathrm{Fe} / \mathrm{F} \mathrm{c}^{+2}}^{\mathrm{o}}=+0.453 \text { volt } ; \ \mathrm{E}_{\mathrm{Cu} / \mathrm{Cu}^{+2}}^{\mathrm{o}}=-0.3435 \text { volt }\end{aligned}$

The quantity of charge required to completely reduce $0.5 \mathrm{~mol}$ of $\mathrm{MnO}_4^{-}$to $\mathrm{Mn}_2 \mathrm{O}_3$ is

The amount of substance deposited by the passage of 1 A of current for 1 s is equal to

$\mathrm{C}{\mathrm{u}^ + }\left( {aq} \right)$ is unstable in solution and undergoes simultaneous oxidation and reduction, according to the reaction
$2\mathrm{C}{\mathrm{u}^ + }\left( {aq} \right)\leftrightharpoons\mathrm{C}{\mathrm{u}^{2 + }}\left( {aq} \right) + \mathrm{Cu}\left( s \right)$
choose correct ${E^ \circ }$ for the above reaction if
$E_{\mathrm{C}{\mathrm{u}^{2 + }}/\mathrm{Cu}}^ \circ = 0.34\mathrm{V},E_{\mathrm{C}{\mathrm{u}^{2 + }}/\mathrm{C}{\mathrm{u}^ + }}^ \circ = 0.15\mathrm{V}$