Reversible Reaction

Contents

Key Stage 4

Meaning

Reversible Reactions are reactions in which the products of that reaction, may themselves react to form the original reactants.

About Reversible Reactions

Reversible reactions use the symbol ⇌ to show that the reaction can happen both ways.

A reaction mixture which can undergo a reversible reaction will reach a state of dynamic equilibrium where there is a constant amount of the reactants and products as the reaction keeps happening in both directions.

Since some reactions may be exothermic and others may be endothermic, then one direction of reaction will provide energy to the environment while the other direction will absorb, that same amount of, energy.

Examples

Hydrogen + Nitrogen ⇌ Ammonia

<chem> 3H2(g) + N2(g) <=> 2NH3(g) </chem>

Calcium Oxide + Carbon Dioxide ⇌ Calcium Carbonate

<chem> CaO(aq) + CO2(g) <=> CaCO3(s) </chem>

Ammonium Chloride ⇌ Ammonia + Hydrochloric Acid

<chem> NH4Cl(s) <=> NH3(g) + HCl(g) </chem>