The following reaction occurs at the anode of an electrochemical cell:
Zn(s) → Zn2+ (aq) + 2e−
Which cathode reaction would produce a battery with the highest voltage?
(a) Mg2+(aq) + 2e− → Mg(s)
(b) Pb2+ (aq) + 2e− → Pb(s)
(c) Cr3+ (aq) + 3e− → Cr(s)
(a) Cu2+ (aq) + 2e− → Cu(s)
Solution: Here, we are going to identify the cathode reaction producing a battery with the highest voltage with the given anode reaction.
Electrochemical cells are the devices which converts chemical energy to electrical energy.
Voltage can be calculated by the following relation:
Ecell = Ecathode – Eanode