Michael Faraday published faraday’s Laws of Electrolysis in 1834.
Faraday’s Second Law of Electrolysis:
”The masses of different substances, liberated or dissolved by the same amount of electricity, are proportional to their equivalent masses.” When the same quantity of electricity is passed through several electrolytic solutions connected in series, then the masses of the different materials liberated or dissolved at the respective electrodes are in the ratio of their equivalent masses.
When the same current is passed through the solutions of sulphuric acid (H2SO4), copper sulphate (CuSO4), and silver nitrate (AgNO3) for the same period of time, then:
- Mass of copper deposited/Mass of silver deposited = Equivalent mass of copper/Equivalent mass of silver and,
- Mass of copper deposited/Mass of hydrogen gas liberated =Equivalent mass of copper/Equivalent mass of hydrogen.
According to the second law of electrolysis, the same quantity of electricity will produce or dissolve chemically equivalent amounts of all the substances. This quantity of electricity is called Faraday (F).
- One Faraday is equal to 96487 coulombs per mole of electronic charges.