Chemistry

Standard Reduction Potentials

The electrode potential is an intensive property whose value is independent of the amount of species in the reaction. Thus, the electrode potential for the following half-reaction is the same for this half-reaction Cu2+ (aq) + 2e → Cu (s) is the same for this half-reaction 2 Cu2+ (aq) + 4e → 2Cu (s).

A voltage cannot be measured just for a half-cell but only for a complete cell. Therefore, to describe the reduction potential for a particular redox couple, the emf is measured for a cell where the other half-cell is a standard reference electrode. The standard reduction potential is in a category known as the standard cell potentials or standard electrode potentials. The standard cell potential is the potential difference between the cathode and anode.

A list of common standard reaction potentials is given below:

a2