$Ksp =\left[ Cu ^{2+}\right]\left[ OH ^{-}\right]^2$
$pH =14 ; pOH =0 ;\left[ OH ^{-}\right]=1\,M$
${\left[ Cu ^{2+}\right]=\frac{ Ksp }{[1]^2}=10^{-20} M }$
$Cu ^{2+}( aq )+2 e ^{-} \rightarrow Cu ( s )$
$E = E ^{\circ}-\frac{0.059}{2} \log _{10} \frac{1}{\left[ Cu ^{2+}\right]}$
$=0.34-\frac{0.059}{2} \log _{10} \frac{1}{10^{-20}}$
$=-0.25=-25 \times 10^{-2}$
આપેલ $\left( E _{ Cu ^{2+} / Cu ^{+}}^{0}=0.16 V \right.$ $,E _{ Cu ^{+} / Cu }^{0}=0.52 V,$ $\left.\frac{ RT }{ F }=0.025\right)$
${{\text{E}}^o }{\text{C}}{{\text{u}}^{{\text{2}} + }}{\text{/Cu = + 0}}{\text{.34 V, E}}_{{\text{F}}{{\text{e}}^{ + {\text{2}}}}/Fe}^o = \,\,{\text{ - 0}}{\text{.44 V}}$