Question

State Faraday’s second law of electrolysis.

Answer 1

Hint:Michael Faraday stated the laws of electrolysis. In order to describe or state this law, first of all you need to consider a few terms such as electrolysis, electrochemical cells and electrodes. The Faraday’s Law of electrolysis gives you the expression, or say, a quantitative relationship between the mass and charge.

Complete answer:
Electrolysis is a process in which the electric current is used to activate a non-spontaneous reaction. This current is produced by the flow of ions in electrolyte. Electrolyte is a conducting liquid.Electrochemical cells are the cells which convert electrical energy into chemical energy. These cells work on electrolysis.

Electrodes are the components of electrochemical cells in which the current flows in or comes out. Due to electrolysis, mass is liberated at the electrode due to the current passing through the electrode. Faraday’s second law of electrolysis gives you the relation between the mass deposited on the electrode and the current passed through.

Faraday’s second law of electrolysis states that “the mass deposited on the electrode due to passing of certain amounts of charges through it is proportional to the chemical equivalent of that substance.” Faraday’s first law states that “the amount of mass deposited is proportional to the amount of charge passed through it.”

Let the chemical equivalent be $E$, the amount of charge passed through it be $q$ and the mass deposited be $m$, we have, $m$ is proportional to $q$ and $E$. Mathematically,$m \propto q$ and $m \propto E$. Combining these two equations, we get, $m \propto qE$
$\therefore m = qE$.
Faraday’s second law of electrolysis states that the mass deposited is proportional to the chemical equivalent.

Note:In order to summarize the concept, remember that the Faraday’s second law of electrolysis gives the relation between mass of substance deposited and the chemical equivalent weight. The chemical weight of a substance is defined as the ratio of atomic weight of the substance and the valency of that substance.