For example: N2 + 3H2 ⇌ 2NH3 In this reaction, once the ammonia (NH 3) has formed, it can ‘go back’ to reform nitrogen and hydrogen. Reversible reactions are shown with reversible arrows (⇌).

Chemical reactions are reversible and may reach a dynamic equilibrium. The position of equilibrium of a reversible reaction can be altered by changing the reaction conditions.