Chemistry - Electrochemistry Question with Solution | TestHub

Key Idea Gibb's free energy is an additive property. $$\Delta {\mathrm{G}}^{\circ }=-{\mathrm{nFE}}^{\circ }$$ For reaction, ${\mathrm{Cu}}^{2+}+2{\mathrm{e}}^{-}⟶\mathrm{Cu}$; $$\Delta G^{\circ }=-2\times \mathrm{F}\times 0.337$$ For reaction, ${\mathrm{Cu}}^{+}⟶{\mathrm{Cu}}^{2+}+{\mathrm{e}}^{-}$; $$\Delta {\mathrm{G}}^{\circ }=+1\times \mathrm{F}\times 0.153$$ Adding Eqs. (i) and (ii), we get $$\begin{array}{c}{\mathrm{Cu}}^{+}+{\mathrm{e}}^{-}⟶\mathrm{Cu};\Delta {\mathrm{G}}^{\circ }=-0.521\\ \Delta {\mathrm{G}}^{\circ }=-{\mathrm{nFE}}^{\circ }\\ -0.521\mathrm{F}=-{\mathrm{nFE}}^{\circ }\\ \therefore {\mathrm{E}}^{\circ }=0.52\mathrm{V}\end{array}$$