Question

what is mean by decomposition reaction ?​

Answer 1

The reaction in which there is only one reactant giving rise to two or more products is called decomposition reaction .

Answer 2

$\huge\tt\colorbox{black}{\color{white}{Answer}}$

Decomposition is usually regarded and defined as the exact opposite of chemical synthesis. In short, the chemical reaction in which two or more products are formed from a single reactant is called a decomposition reaction.