In chemistry, the electrochemical equivalent (Eq or Z) of a chemical element is the mass of that element (in grams) transported by a specific quantity of electricity, usually expressed in grams per coulomb of electric charge.^[1] The electrochemical equivalent of an element is measured with a voltameter.

Definition

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

${\displaystyle Z=M/It}$

Eq values of some elements in kg/C