Electro chemistry practice · Medium

The increase in equivalent conductivity of a weak electrolyte solution with dilution is attributed to :

Equivalence conductance at infinite dilution of ${NH}_4 {Cl}, {NaOH}$ and ${NaCl}$ are $129.8, 217.4$ and $108.9 \, \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1},$ respectively. If the equivalent conductance of $0.01 \mathrm{~N}$ solution of ${NH}_4 {OH}$ is $9.532 \, \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1},$ then the degree of dissociation of ${NH}_4 {OH}$ at this temperature is

The reduction potential of a hydrogen electrode having $\mathrm{pH}$ value '${x}$' and ${y}$ atm pressure of ${H}_2$-gas at $25^{\circ} \mathrm{C}$ is correctly given as

Statement I: When iron rod is immersed in $\mathrm{NaCl}$ solution such that half of its length is corroded and other half part when exposed to air is not corroded.

Statement II: Metal portion with less access to $\mathrm{O}_2$ corrodes.

A current of 9.65 flowing for 10 minute deposits 3.0 g of a metal. The equivalent weight of the metal is

STATEMENT-1 : We cannot add the electrode potential in order to get electrode potential of third electrode if no. of moles of electrons exchanged are not same.
STATEMENT-2 : Electrode potential is an extensive property.

The potential difference of two electrodes in a galvanic cell is known as

What is the density of solution of sulphuric acid used as on electrolyte in lead accumulator

The standard potentials of ${OCl}^{-} / {Cl}^{-}$ and ${Cl}^{-} / {Cl}_2$ are $0.94 \mathrm{~V}$ and $-1.36 \mathrm{~V},$ respectively. The $E^{\circ}$ value of ${OCl}^{-} / {Cl}_2$ will be

Statement I: In case of $\mathrm{Hg}$ cathode $\mathrm{Na}$ undergoes deposition
Statement II: Nature of electrode determines the deposition order

The conductivity of $N/50$ solution of $\mathrm{KCl}$ in a cell at 250C is $0.002765{\kern 1pt} {\kern 1pt} {\rm{mho {\kern 1pt}{\kern 1pt} c}}{\mathrm{m}^{ - 1}}$ . If the resistance of a cell containing this solution is 400 ohm, the cell constant is :

For the given reactions

$\mathrm{S n}^{2+}+2 \mathrm{e}^{-} \rightarrow \mathrm{S n}$

$\mathrm{S n}^{4+}+2 \mathrm{e}^{-} \rightarrow \mathrm{S n}$

The electrode potentials are; $\mathrm{E}_{\mathrm{Sn}^{2+} / \mathrm{Sn}}^0=-0.140\text{ V}$ and $\mathrm{E}_{\mathrm{Sn}^{4+} / \mathrm{Sn}}^{\circ}=0.010 \mathrm{~V}.$ The magnitude of standard electrode potential for $\mathrm{Sn}^{4+} / \mathrm{Sn}^{2+}$ i.e. $\mathrm{E}_{\mathrm{Sn}^{4+} / \mathrm{Sn}^{2+}}$ is _____ $\times{10^{-{2}} \mathrm{V}}.$

How much metal will be deposited when a current of 12 ampere with $75 \%$ efficiency is passed through the cell for $3 \mathrm{~h}$? (Given: ${Z}=4 \times 10^{-4}$)

For the galvanic cell

$\mathrm{Cr}(\mathrm{s})\left|\mathrm{Cr}^{3+}\left(2.23 \times 10^{-7} \mathrm{M}\right) \| \mathrm{Ag}^{+}(0.0264 \mathrm{M})\right| \mathrm{Ag}(\mathrm{s})$ at $25^{\circ} \mathrm{C}$

Calculate the emf of the cell.

Given: $\mathrm{E}^{\circ}\left(\mathrm{Ag}^{+} / \mathrm{Ag}\right)=0.80 \mathrm{~V}$

$\mathrm{E}^{\circ}\left(\mathrm{Cr}^{+3} / \mathrm{Cr}\right)=-0.74 \mathrm{~V}$

Using a particular conductivity cell, resistance offered is $60 \Omega$. When the conductivity cell with area twice the earlier and having $75 \%$ more distance between the electrodes is used, resistance offered will be

On which factor, electrical conductivity of electrolytic cell doesn’t depend

During electrolysis of sulphuric acid, which of the following processes is possible at anode?

A. $2 {H}_2 {O}({l}) \longrightarrow {O}_2({~g})+4 {H}^{+}({aq})+4 {e}^{-} \stackrel{\ominus}{{E}_{\text {cell }}}=+1.23 {~V}$

B. $2 {SO}_4^{2-}({aq}) \longrightarrow {S}_2 {O}_8^{2-}({aq})+2 {e}^{-} \stackrel{\ominus}{{E}_{\text {cell }}}= 1.96 {~V}$

Choose the correct option based on following statements.

(i) Process A is preferred at higher concentration of sulphuric acid.

(ii) Process B is preferred at higher concentration of sulphuric acid.

(iii) Process A is preferred for dilute sulphuric acid.

(iv) Process B is preferred for dilute sulphuric acid.

(v) Both A and B are equally possible at higher concentration.

The amount of charge that must be passed through a solution containing $\mathrm{Cu}^{2+}$ in order to deposit $1 \mathrm{~g}$ atom of copper $(63.55)$ is

A cell constructed by coupling a standard copper electrode and a standard magnesium electrode has emf of 2.7 V. If the standard reduction potential of copper electrode is +0.34 V then that of the magnesium electrode is

The Gibbs energy change (in KJ) for the given reaction at $\left[ {C{u^{2 + }}} \right] = \left[ {S{n^{2 + }}} \right] = 1M$ and 298 K is $Cu\left( s \right) + S{n^{2 + }}\left( {aq} \right) \to C{u^{2 + }}\left( {aq} \right) + SN\left( s \right);\,\left( {E_{S{n^{2 + }}/Sn}^0 = - 0.16V,\,E_{C{u^{2 + }}/Cu}^0 = 0.34V} \right)$
Take, $F = 96500\,\,\,C\,\,mo{l^{ - 1}}$)

When an acid cell is charged, then

When a lead storage battery is charged

How much current is necessary to produce $\mathrm{H}_2$ gas at the rate of $1 \mathrm{~cm}^3$ per second under STP.

Chlorine gas is passed into a solution containing KF, KI, and KBr and $\mathrm{CHC}{\mathrm{l}_3}$ is added. The initial colour in $\mathrm{CHC}{\mathrm{l}_3}$ layer is :

How does the electrical conductivity of $20 \mathrm{~ml}$ of $0.2 \mathrm{~M}-\mathrm{MgSO}_4$ change when $0.5 \mathrm{~M}-\mathrm{Ba}(\mathrm{OH})_2$ solution is gradually added in it, to excess?

STATEMENT-1 : When 2 faraday of electricity is passed through $0.1 \mathrm{~M} \mathrm{~H}_2 \mathrm{SO}_4(\mathrm{aq}), 11.2$ litre $\mathrm{O}_2$ evolved at STP.

STATEMENT-2 : Molecular weight of oxygen is 32 .

The products formed when an aqueous solution of ${NaBr}$ is electrolysed in a cell having inert electrodes are:

During electrolysis of water the volume of ${\mathrm{O}_2}$ liberated is 2.24 $\mathrm{d}{\mathrm{m}^3}$. The volume of hydrogen liberated, under same conditions will be

By how much would the oxidizing power of $\mathrm{MnO}_4{ }^{-} / \mathrm{Mn}^{2+}$ couple change if the $\mathrm{H}^{+}$ ions concentration is decreased 100 times at $25^{\circ} \mathrm{C}?$

In the electrolysis of water, 1 F of electrical energy would evolve