A half-cell is half of an electrolytic or voltaic cell, where either oxidation or reduction occurs. The half-cell reaction at the anode is oxidation, while the half-cell reaction at the cathode is reduction.
Half-Cell Example
The electrochemical reaction of a Daniell cell may be written as two half-cells. The original equation is:
2H+(aq) + 2e- → H2(g)
The half-cells or half-reactions are:
Zn → Zn2+ + 2e− (for the reaction at the anode or Zn)
Cu2+ + 2e− → Cu (for the reaction at the cathode or Cu)
Source
- Andrews, Donald H.; Richard J. Kokes (1962). "Electrochemistry." Fundamental Chemistry. New York: John Wiley & Sons, Inc.