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Neutralisation Reaction - GCSE Chemistry Definition

Reviewed by: Richard Boole

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A neutralisation reaction is a chemical reaction in which an acid reacts with an alkali (or base) to form a salt and water. It happens when hydrogen ions (H+) from the acid combine with hydroxide ions (OH-) from the alkali to form water (H2O), which is neutral:

H+ + OH- → H2O

This reaction cancels out the properties of both the acid and alkali. A typical example is when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH) to form sodium chloride (common table salt) and water:

hydrochloric acid + sodium hydroxide → sodium chloride + water

(HCl) + (NaOH) → (NaCl) + (H2O)

Neutralisation reactions are useful in everyday life, such as treating indigestion with antacids, or adjusting soil pH in agriculture.

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Richard Boole

Reviewer: Richard Boole

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