7. Calculate the free energy change per mole of Cu2+ formed in the following reaction at 25 °C.
Cu + 2 Ag+ -> 2 Ag + Cu2+,
Cu2+ + 2 e -> Cu E° = 0.34 V;
Ag* + e* -> Ag, E° = 0.80 V.
(a) 0.46 kJ
(b) 89 kJ
(c) 44.5 kJ
(d) -89 kJ