Consider the following reaction :
Mg + 2Ag+ â†" 2 Ag + Mg2+
E0Mg2+/Mg = -2.36 V,E0Ag+/Ag = 0.80 V. The cell potential for this cell will be:
3.16 V
The cell potential is the difference between the reduction potential of cathode and anode.
E0cell = E0cathode – E0anode