Hydrogen Ion (Chemistry)

Key Stage 4

A Hydrogen ion (H⁺), sometimes called a proton, is a positive ion of Hydrogen found in acid solutions.

When an acid compound dissolves in water it forms Hydrogen ions.

Hydrogen ions are responsible for the corrosive properties of acids.

As the pH of a solution decreases by 1 the Hydrogen ion concentration increases by a factor of 10.

Some acids are so strong that all of the Hydrogen ions become dissociated from the rest of the compound.

HCl(aq) → H⁺(aq)+Cl^-(aq)

In many acids not all of the molecules will lose their Hydrogen ions and this process can be reversed leaving them in a state of equilibrium:

H₂SO₄(aq) ⇌ H⁺(aq)+HSO₄^-(aq)

HNO₃(aq) ⇌ H⁺(aq)+NO₃^-(aq)

H₂CO₃(aq) ⇌ H⁺(aq)+HCO₃^-(aq)

H₃PO₄(aq) ⇌ H⁺(aq)+H₂PO₄^-(aq)

CH₃COOH(aq) ⇌ H⁺(aq)+CH₃COO^-(aq)