Question

The catalyst present in the decomposition of hydrogen peroxide is ferrous sulphate or phosphoric acid or both?

Answer 1

Ferrous sulphate is used as a catalyst in decomposition of hydrogen peroxide and not phosphoric acid.

In fact Phosphoric acid acts as a negative catalyst.

Negative catalysts (inhibitors) are those substances which slow down the chemical reactions by decreasing the required activation energy for the reaction, for example the decomposition of Hydrogen peroxide may be slow down by adding a small amount of phosphoric acid in it.