(a) Faraday’s second law of electrolysis :
The amount of different substances liberated by the same quantity of electricity passing through the electrolytic solution are proportional to their chemical equivalent weights.
(b) Corrosion : The coating of surfaces of metallic objects with oxides or other salts of the metal is called corrosion.
Some examples of corrosion are rusting of iron, tarnishing of silver and development of green coating on copper and bronze.
