What is the free energy change per mole of Cu (II) ion formed in a cell consisting of Cu | Cu (II) ion half-cell suitably connected to a Ag | Ag⁺ ion half-cell? (Given: E° = 0.46 V)

a) -0.46 V
b) 0.46 V
c) -0.23 V
d) 0.23 V