Why are decomposition reactions called the opposite of combination reactions ? Write equations for these reactions.

Explanation

In a decomposition reaction a single reactant gives two or more products, whereas, in a combination reaction two or more reactants combine to give a single product ? Hence, the decomposition reactions are the opposite of combination reactions .
e.g. : `2H_(2)Ooverset("electric current")(to)2H_(2)+O_(2)` - decomposition reaction.
`2H_(2)+O_(2)to2H_(2)O`- combination reaction