half-reaction

In chemistry, a half reaction (or half-cell reaction) is either the oxidation or reduction reaction component of a redox reaction. A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction. Often, the concept of half reactions is used to describe what occurs in an electrochemical cell, such as a Galvanic cell battery at one of the two electrodes.

In the case of metal plating and metal stripping the same half reaction can be written to describe both the metal undergoing oxidation (known as the anode) and the metal undergoing reduction (known as the cathode).