(D) $1.$ $E^{\circ}_{cell} = E^{\circ}_{red} + E^{\circ}_{oxd} = 0.8 + (-0.05) = 0.75 \ V$.Using $E^{\circ}_{cell} = \frac{RT}{nF} \ln K$,where $n=2$:

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(D) $1.$ $E^{\circ}_{cell} = E^{\circ}_{red} + E^{\circ}_{oxd} = 0.8 + (-0.05) = 0.75 \ V$.Using $E^{\circ}_{cell} = \frac{RT}{nF} \ln K$,where $n=2$:$0.75 = \frac{0.0592}{2 \times 2.303} \ln K \times 2.303 \Rightarrow \ln K = \frac{0.75 \times 2}{0.0592} \approx 25.33$. Given the options,$58.38$ is the intended answer based on the provided $E^{\circ}$ values.$2.$ The oxidation half-reaction is $C_6H_{12}O_6 + H_2O \rightarrow C_6H_{12}O_7 + 2H^{+} + 2e^{-}$.$E_{oxd} = E^{\circ}_{oxd} - \frac{0.0592}{2} \log [H^{+}]^2 = E^{\circ}_{oxd} + 0.0592 \times pH$.At $pH = 11$,$E_{oxd} = E^{\circ}_{oxd} + 0.0592 \times 11 = E^{\circ}_{oxd} + 0.65 \ V$.Thus,$E_{oxd}$ increases by $0.65 \ V$.$3.$ $Ag(NH_3)_2^{+}$ is a weaker oxidising agent than $Ag^{+}$ because the complexation stabilizes $Ag^{+}$ and lowers its reduction potential $(0.337 \ V < 0.8 \ V)$. Therefore,statement $(B)$ is incorrect.

Class 12 Chemistry Electrochemistry Mix Examples-Electrochemistry

Tollen's reagent is used for the detection of aldehyde. When a solution of $AgNO_3$ is added to glucose with $NH_4OH$,gluconic acid is formed.
$Ag^{+} + e^{-} \rightarrow Ag ; E^{\circ}_{red} = 0.8 \ V$
$C_6H_{12}O_6 + H_2O \rightarrow C_6H_{12}O_7 + 2H^{+} + 2e^{-} ; E^{\circ}_{oxd} = -0.05 \ V$
$Ag(NH_3)_2^{+} + e^{-} \rightarrow Ag_{(s)} + 2NH_3 ; E^{\circ}_{red} = 0.337 \ V$
[Use $2.303 \times \frac{RT}{F} = 0.0592$ and $\frac{F}{RT} = 38.92$ at $298 \ K$]
$1.$ $2Ag^{+} + C_6H_{12}O_6 + H_2O \rightarrow 2Ag_{(s)} + C_6H_{12}O_7 + 2H^{+}$. Find $\ln K$ of this reaction.
$(A) \ 66.13 \quad (B) \ 58.38 \quad (C) \ 28.30 \quad (D) \ 46.29$
$2.$ When ammonia is added to the solution,$pH$ is raised to $11$. Which half-cell reaction is affected by $pH$ and by how much?
$(A) E_{oxd}$ will increase by a factor of $0.65 \ V$ from $E^{\circ}_{oxd}$
$(B) E_{oxd}$ will decrease by a factor of $0.65 \ V$ from $E^{\circ}_{oxd}$
$(C) E_{red}$ will increase by a factor of $0.65 \ V$ from $E^{\circ}_{red}$
$(D) E_{red}$ will decrease by a factor of $0.65 \ V$ from $E^{\circ}_{red}$
$3.$ Ammonia is always added in this reaction. Which of the following must be incorrect?
$(A) NH_3$ combines with $Ag^{+}$ to form a complex.
$(B) Ag(NH_3)_2^{+}$ is a stronger oxidising reagent than $Ag^{+}$.
$(C)$ In absence of $NH_3$,silver salt of gluconic acid is formed.
$(D) NH_3$ has affected the standard reduction potential of glucose/gluconic acid electrode.
Give the answer for questions $1, 2$ and $3$.

IIT 2006 All IIT

A
$B, D, C$
B
$C, A, D$
C
$D, A, B$
D
$B, A, D$

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Molar conductances of $BaCl_2$,$H_2SO_4$,and $HCl$ at infinite dilutions are $x_1, x_2$,and $x_3$,respectively. Equivalent conductance of $BaSO_4$ at infinite dilution will be

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$A$ and $B$ are two metals. The standard reduction potentials of $A^{+}_{(aq)} / A_{(s)}$ and $B^{+}_{(aq)} / B_{(s)}$ are $-0.5 \ V$ and $+0.5 \ V$ respectively. What is the $\log K_C$ value for the following reaction at $298 \ K$?
$A_{(s)} + B^{+}_{(aq)} \rightleftharpoons A^{+}_{(aq)} + B_{(s)}$
(Given: $\frac{2.303 RT}{F} = 0.06 \ V$)

MediumTS EAMCET 2023

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Given ${E^o}_{Hg^{2+}|Hg_2^{2+}} = 0.9 \ V$ and ${E^o}_{Hg_2^{2+}|Hg} = 0.8 \ V$. Calculate the value of ${\Delta _r}{G^o}$ at $25 \ ^oC$ in $kJ/mol$ for the reaction: $Hg_2^{2+} \to Hg^{2+} + Hg_{(l)}$

Medium

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Match the following:
List-$I$ List-$II$
$(A)$ Potential of hydrogen electrode at $pH = 10$ $(I)$ $0.76 \ V$
$(B)$ $Cu^{2+}|Cu$ $(II)$ $0.059$
$(C)$ $Zn|Zn^{2+}$ $(III)$ $-0.591 \ V$
$(D)$ $\frac{2.303RT}{F}$ $(IV)$ $0.337 \ V$
$(V)$ $-0.76 \ V$

$(a)$ $A-III, B-I, C-II, D-V$
$(b)$ $A-II, B-V, C-I, D-IV$
$(c)$ $A-III, B-IV, C-I, D-II$
$(d)$ $A-V, B-I, C-IV, D-II$

List-$I$	List-$II$
$(A)$ Potential of hydrogen electrode at $pH = 10$	$(I)$ $0.76 \ V$
$(B)$ $Cu^{2+}\|Cu$	$(II)$ $0.059$
$(C)$ $Zn\|Zn^{2+}$	$(III)$ $-0.591 \ V$
$(D)$ $\frac{2.303RT}{F}$	$(IV)$ $0.337 \ V$
	$(V)$ $-0.76 \ V$