Neutralisation reaction is a

A neutralization reaction is a chemical change that cannot be reversed.
A neutralization reaction is a chemical reaction in which an acid and a base react quantitatively to form salt and water as products. A neutralization reaction involves the formation of water by the combination of $H^{+}$ ions and ${\mathit{OH}}^{-}$ ions. For example, when a strong acid, $\mathit{HCl}$ (Hydrochloric acid), reacts with a strong base, $\mathit{NaOH}$, the resulting salt is sodium chloride and water. The reaction is as follows:
$\mathit{NaOH}+\mathit{HCl}\to \mathit{NaCl}+H_{2}O$