A + BC → AC + B

In this equation, A is a reactive metal that displaces a less reactive metal B from its compound BC. The products of the reaction are a new compound AC and the displaced metal B.

For example, when iron (Fe) reacts with copper sulfate (CuSO4), the iron displaces the copper from the sulfate, forming iron sulfate (FeSO4) and copper metal (Cu).

Fe + CuSO4 → FeSO4 + Cu

Single-displacement reactions are also known as substitution reactions because one element is substituted for another in a compound.