Why is decomposition reaction called the opposite of combination reaction? The equations for these reactions...

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

(a) Why are decomposition reactions called the opposite of combination reactions ? Explain with equations of these reactions. (b) Express the following facts in the form of a balanced chemical equation: "When a strip of copper metal is placed in a solution of silver nitrate, metallic silver is precipitated and a solution containing copper nitrate is formed"

What is a combination reaction ?

……………. is a decomposition reaction.