At the reduction-electrode this reaction takes place, A2+ + 2e- ⇔ A.…

E = E^o_A2+/A - \(\frac{RT}{2F}\)ln\(\frac{[A]}{[A^{2+}]}\)

E = E^o_A2+/A + \(\frac{RT}{2F}\)ln\(\frac{[A]}{[A^{2+}]}\)

E = E^o_A2+/A + \(\frac{RT}{F}\)ln\(\frac{[A]}{[A^{2+}]}\)

E = E^o_A2+/A - \(\frac{RT}{F}\)ln\(\frac{[A]}{[A^{2+}]}\)