E^o_{cell} for the cell: Pt_{(s)} | H_{2(g)} | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The cell reaction is: $CH_3COOH + HCOO^- \rightleftharpoons CH_3COO^- + HCOOH$.The equilibrium constant for this reaction is $K_{eq} = \frac{K_a(C

Vedclass · Accepted Answer

$-0.0672$

Vedclass · Answer

(B) The cell reaction is: $CH_3COOH + HCOO^- ightleftharpoons CH_3COO^- + HCOOH$.The equilibrium constant for this reaction is $K_{eq} = \frac{K_a(CH_3COOH)}{K_a(HCOOH)} = \frac{1.8 	imes 10^{-5}}{2.4 	imes 10^{-4}} = 0.075$.Using the relation $E^o_{cell} = \frac{0.059}{n} \log K_{eq}$ at $25^oC$ (where $n=1$):$E^o_{cell} = 0.06 	imes \log(0.075) = 0.06 	imes \log(\frac{3}{40}) = 0.06 	imes (\log 3 - \log 40) = 0.06 	imes (0.477 - 1.602) = 0.06 	imes (-1.125) = -0.0675 \ V$.Given the approximation $\frac{2.303RT}{F} = 0.06$,the value is approximately $-0.0672 \ V$.

$E^o_{cell}$ for the cell: $Pt_{(s)} | H_{2(g)} | HCOOH_{(aq)} || CH_3COOH_{(aq)} | H_{2(g)} | Pt_{(s)}$ at $25^oC$ is ............ $V$. ($K_a$ of $HCOOH = 2.4 \times 10^{-4}$,$K_a$ of $CH_3COOH = 1.8 \times 10^{-5}$,$\log 2 = 0.3$,$\log 3 = 0.477$,$\frac{2.303RT}{F} = 0.059$ or $0.06$)

Similar Questions

The $EMF$ of a cell whose half-cell reactions are given below is .......... $V$.
$Mg^{2+} + 2e^- \to Mg_{(s)}; E^o = -2.37 \ V$
$Cu^{2+} + 2e^- \to Cu_{(s)}; E^o = +0.34 \ V$ (in $V$)

For the cell reaction:
$2 Fe^{3+}_{(aq)} + 2 I^{-}_{(aq)} \rightarrow 2 Fe^{2+}_{(aq)} + I_{2(aq)}$
$E^{\ominus}_{cell} = 0.24 \ V$ at $298 \ K$. The standard Gibbs energy $(\Delta_r G^{\ominus})$ of the cell reaction in $kJ \ mol^{-1}$ is:
[Faraday constant $F = 96500 \ C \ mol^{-1}$]

The standard electrode potentials are: $K^{+}/K = -2.93 \ V$,$Ag^{+}/Ag = 0.80 \ V$,$Hg^{2+}/Hg = 0.79 \ V$,$Mg^{2+}/Mg = -2.37 \ V$,$Cr^{3+}/Cr = -0.74 \ V$. Arrange these metals in the increasing order of their reducing power.

$A$ cell is constructed by dipping a copper rod in $1\,M\,CuSO_4$ solution and a nickel rod in $1\,M\,NiSO_4$ solution. The standard reduction potentials of copper and nickel electrodes are $+0.34\,V$ and $-0.25\,V$ respectively. Calculate the $EMF$ of the cell. (in $,V$)

If the $\Delta G$ of a cell reaction $AgCl + e^- \to Ag + Cl^{-}$ is $-21.20 \ kJ$,the standard e.m.f. of the cell is ............ $V$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module