Question

Why is the electrolysis of sulphuric acid called electrolysis of water?

Answer 1

As we know that sulphuric acid is a chemical compound having the molecular formula ${H_2}S{O_4}$. This acid is also known as oil of vitriol and it is a mineral acid which contains the elements hydrogen, sulphur and oxygen. And the sulphuric acid does not have any colour and smell and it is miscible in water. The electrolysis process contains the electricity. The electricity will break down the electrolytes and there is a formation of elements.

Complete answer:
We need to know that the electrolysis of sulphuric acid is called electrolysis of water. Because, the diluted sulphuric acid is also known as acidic water. Because it contains water. The ions present in the water are ${H^ + }$ and $O{H^ - }$. And the sulphuric acid contains the ions ${H^ + }$ and $SO_4^ -$. The water and sulphuric acid will mix to increase the number of ions. Hence, the electrolysis of sulphuric acid is also known as the electrolysis of water. When the water is added to the sulphuric acid, it will dissociate into ${H^ + }$ and $O{H^ - }$ ions and it will conduct the electricity. Here, the cathode will attract the hydrogen ions and two negative ions are attracted by the anode. But the hydroxide ions will lose the electrons. Thus water is made into a conductive solution by adding sulphuric acid.

Note:
We need to remember that the electrolysis of sulphuric acid is conducted in the presence of platinum electrodes. Then the anode will liberate the oxygen gases and the hydrogen ions are attracted by the cathode. The mixture of sulphuric acid and water will help to introduce the ions and the ions will increase the conductance of the water and it makes reaction very faster. But it does not influence the chemical composition of the product and the reactant. It only increases the speed of the reaction.