Electro chemistry practice · Mixed difficulty

In following cell reaction

${Mg}({s})+2 {Ag}^{+}(0.001 {M}) \longrightarrow {Mg}^{2+}(0.20 {M})+2 {Ag}({s})$

Calculate $E_{\text {cell }}$ for the reaction $\left[E^0=3.17 {~V}\right]$

$\mathrm{Sn}^{4+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Sn}^{2+} E^{\circ}=0.13 \mathrm{~V}$

$\mathrm{Br}_2+2 \mathrm{e}^{-} \longrightarrow 2 \mathrm{Br}^{-} \quad E^{\circ}=1.08 \mathrm{~V}$

Calculate $K_{\mathrm{eq}}$ for the cell formed by two electrodes

Four successive members of the first row transition elements listed below with atomic numbers. Which one of them is expected to have the highest $E_{{M^{3 + }}/{M^{2 + }}}^ \circ$ value is?

If the molar conductivity of $10^{-3} \mathrm{~M} \mathrm{~HA}$ is $39 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1},$ then its dissociation constant will be

[Given $\Lambda_{\mathrm{m}}^0(\mathrm{HA})=390 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1}]$

In acidic medium $\mathrm{MnO}_4^ -$ is converted to $\mathrm{M}{\mathrm{n}^{2 + }}$ . The quantity of electricity in faraday required to reduce 0.5 mole of $\mathrm{MnO}_4^ -$ to $\mathrm{M}{\mathrm{n}^{2 + }}$ would be

$E^\circ$ values of some redox couples are given below on the basis of these values. Choose the correct option
$E^\circ$ values:
$\begin{array}{l} B{r_2}\mathrm{/}B{r^ - } = + 1.90\\ A{g^ + }\mathrm{/}Ag(s) = + 0.80\\ C{u^{2 + }}\mathrm{/}Cu(s) = + 0.34\\ {I_2}(s)\mathrm{/}{I^ - } = + 0.54 \end{array}$

During the electrolysis of a solution of $\mathrm{AgN}{\mathrm{O}_3},9650\mathrm{C}$ of charge is passed through the electroplating bath.
The mass of silver deposited at the cathode will be

The equivalent conductance of an aqueous solution of $1.0283 \times 10^{-3} \mathrm{~g}$ equivalent acetic acid per litre is $48.15 \pi^{-1} \mathrm{~cm}^2$ equiv $^{-1}$ at $25^{\circ} \mathrm{C}$. At infinite dilution value is $390.7 \pi^{-1} \mathrm{~cm}^2$ equiv ${ }^{-1}$. Calculate the degree of ionisation and ionisation constant of acetic acid.

The oxidation potential of Mg and Al are + 2.37 and + 1.66 volt respectively. The Mg in chemical reactions :

Which of the following electrolytes is used in lead storage battery?

On the basis of the information available from the $\frac{4}{3} \mathrm{Al}+\mathrm{O}_2 \longrightarrow \frac{2}{3} \mathrm{Al}_2 \mathrm{O}_3, \Delta G=-827 \mathrm{~kJ} \mathrm{~mol}^{-1}$ of $\mathrm{O}_2$, the minimum emf required to carry out an electrolysis of $\mathrm{Al}_2 \mathrm{O}_3$ is : $\left(\mathrm{F}=96500 \mathrm{~C} \mathrm{~mol}^{-1}\right.$ )

In a fuel cell hydrogen and oxygen react to produce electricity. In the process hydrogen gas is oxidised at the anode and oxygen at the cathode. If $67.2 \mathrm{~L}$ of $\mathrm{H}_2$ at STP react in 15 minutes, what is the average current produced ? If the entire current is used for electrodeposition of copper from copper (II) solution, how many grams of copper will be deposited ?

Anode reaction : $\mathrm{H}_2+2 \mathrm{OH}^{-} \longrightarrow 2 \mathrm{H}_2 \mathrm{O}+2 \mathrm{e}^{-}$

Cathode reaction: $\mathrm{O}_2+2 \mathrm{H}_2+2 \mathrm{e}^{-} \longrightarrow 4 \mathrm{OH}^{-}$

Select the correct statement(s) for the given reaction.

$\mathrm{Cu}(s)+2 \mathrm{Ag}^{+}(a q) \longrightarrow \mathrm{Cu}^{2+}(a q)+2 \mathrm{Ag}(s)$

The electrical conductivity of the flowing aqueous solutions is highest for:

$\mathrm{KCl}\left( {aq} \right)$ cannot be used as a salt bridge for the cell $\mathrm{Cu}\left( s \right)\left| {\mathrm{CuS}{\mathrm{O}_4}\left( {aq} \right)} \right|\left| {\mathrm{AgN}{\mathrm{O}_3}\left( {aq} \right)} \right|\mathrm{Ag}\left( s \right)$ because :

A steady current of 30.0 A for 70.2 min corresponds to a
passage of

A galvanic cell : $\mathrm{Cu}\left|\mathrm{Cu}^{2+}\right|\left|\mathrm{Ag}^{+}\right| \mathrm{Ag}$ initially contains $1 \mathrm{~M}\mathrm{~Ag}^{+}$and $1 \mathrm{~M} \mathrm{~Cu}^{2+}$ ions. The cell potential after the passage of $9.65 \mathrm{~A}$ of current for $1 \mathrm{~h}$ will be ___ V.

Assertion (A): $\Lambda_m$ for weak electrolytes shows a sharp increase, when the electrolytic solution is diluted.

Reason (R): For weak electrolytes degree of dissociation increases with dilution of solution.

Consider the following reaction :

$2\mathrm{A}{\mathrm{g}^ + }{\mathrm{C}_6}{\mathrm{H}_{12}}{\mathrm{O}_6} + {\mathrm{H}_2}\mathrm{O} \to 2\mathrm{Ag}\left( s \right) + {\mathrm{C}_6}{\mathrm{H}_{12}}{\mathrm{O}_7} + 2{\mathrm{H}^ + }$

When ammonia is added to the solution, pH is raised to 11. Which half-cell reaction is affected by pH and by how much?

$\mathrm{A}{\mathrm{g}^ + } + {e^ - } \to \mathrm{Ag};E_{\mathrm{red}}^ \circ = 0.8\mathrm{V}$

${\mathrm{C}_6}{\mathrm{H}_{12}}{\mathrm{O}_6} + {\mathrm{H}_2}\mathrm{O} \to {\mathrm{C}_6}{\mathrm{H}_{12}}{\mathrm{O}_7} + 2{\mathrm{H}^ + } + 2{e^ - };E_{\mathrm{red}}^ \circ = - 0.05\mathrm{V}$

$\mathrm{Ag}\left( {\mathrm{N}{\mathrm{H}_3}} \right)_2^ + + {e^ - } \to \mathrm{Ag}\left( s \right) + \mathrm{N}{\mathrm{H}_3};E_{\mathrm{red}}^ \circ = 0.337\mathrm{V}$

$2 \mathrm{MnO}_4^{-}+\mathrm{aH}^{+}+\mathrm{bH}_2 \mathrm{O}_2 \longrightarrow 2 \mathrm{Mn}^{+2}+\mathrm{cH}_2 \mathrm{O}+\mathrm{dO}_2$. What are the values of $\mathrm{a}, \mathrm{b}, \mathrm{c}$ and $\mathrm{d}$?

The correct order of molar conductance at infinite dilution of ${NaCl}, {KCl}, {RbCl}$ is

$\mathrm{KCl}\left( {aq} \right)$ cannot be used as a salt bridge for the cell $\mathrm{Cu}\left( s \right)\left| {\mathrm{CuS}{\mathrm{O}_4}\left( {aq} \right)} \right|\left| {\mathrm{AgN}{\mathrm{O}_3}\left( {aq} \right)} \right|\mathrm{Ag}\left( s \right)$ because :

Given, $\mathrm{E}^{\circ}=-0.27 \mathrm{~V}$ for the $\mathrm{Cl}^{-}\left|\mathrm{PbCl}_2\right| \mathrm{Pb}$ couple and $0.12 \mathrm{~V}$ for the $\mathrm{Pb}^{2+} \mid \mathrm{Pb}$ couple, determine $\mathrm{K}_{\mathrm{sp}}$ for $\mathrm{PbCl}_2$ at $25^{\circ} \mathrm{C}$ ? (Take $\frac{2.303 R T}{F}=0.06$ )

Following is the concentration cell in which electrode is
reversible with respect to anion
$\mathop {Pt\left( {C{l_2}} \right)}\limits_{1\,\,{\text{bar}}} \left| {C{l^ - }\left( {{C_1}} \right)} \right|\left| {C{l^ - }\left( {{C_2}} \right)} \right|\mathop {Pt\left( {C{l_2}} \right)}\limits_{1\,\,{\text{bar}}}$
The cell reaction is spontaneous, if

Assertion (A): ${KMnO}_4$ act as only oxidizing agent.

Reason (R): In ${KMnO}_4, {Mn}$ is in its highest oxidation state +7.

Assertion: The cell constant of a cell depends upon the nature of the material of the electrodes.

Reason: The observed conductance depends upon the nature of the electrolyte and the concentration of the solution.

The position of some metals in the electrochemical series in decreasing electropositive character is given as $\mathrm{Mg} > Al > Zn > Cu > Ag$. What will happen, if a copper spoon is used to stir a solution of aluminium nitrate?

The laws of electrolysis were proposed by

Red hot carbon will remove oxygen from the oxides XO, and YO but not from ZO. Y will remove oxygen from XO. Use this evidence to reduce the order of activity of the three metals X, Y and Z putting the most reactive first:

Rust is