The electrochemical equivalent of a substance is the mass of the substance deposited to one of the electrodes when a current of 1 ampere is passed for 1 second, i.e. a quantity of electricity of one coulomb is passed.

The formula for finding electrochemical equivalent is as follows:

${\displaystyle Z=M/q}$ 

where ${\displaystyle M}$  is the mass of substance and ${\displaystyle q}$  is the charge passed. Since ${\displaystyle q=It}$ , where ${\displaystyle I}$  is the current applied and ${\displaystyle t}$  is time, we also have

${\displaystyle Z=M/It}$