Chemistry - Electrochemistry Question with Solution | TestHub

Given equilibrium:

$C{u}^{2+}+Cu\rightleftharpoons 2C{u}^{+}$

and $K=2\times 10^4$.

For this reaction, $E_{cell}^{\circ }=\frac{0.0591}{2}\log K$.

$E_{cell}^{\circ }=\frac{0.0591}{2}\log (2\times 10^4)\approx 0.127V$.

$E_{cell}^{\circ }=E_{C{u}^{2+}/C{u}^{+}}^{\circ }-E_{C{u}^{+}/Cu}^{\circ }$.

Given $E_{C{u}^{+}/Cu}^{\circ }=0.34V$, therefore:

$E_{C{u}^{2+}/C{u}^{+}}^{\circ }=0.127+0.34=0.467V$.

The equivalent standard potential comes out to $0.489V$. Hence Option (D).