Question
Calculate the cell e.m.f. at 25° C for the following cell:
Mg(s) | Mg2+ (0.01 M) || Sn2+ (0.1 M) | Sn (s)
[Given E°Mg2+/Mg = – 2.34 V, E°Sn2+/Sn = – 0.136V, 1 F = 96,500 C mol–1]
Calculate the maximum work that can be accomplished by the operation of this cell.
Solution
Mg(s) | Mg2+ (0.01 M) || Sn2+ (0.1 M) | Sn(s)
Mg(s) → Mg2+ (aq) + 2e–
(oxidation at anode)
Sn2+(aq) + 2e– → Sn(s)
(reduction at cathode)