Question

Write the chemical formula of ammonium chloride. Explain why an aqueous solution of ammonium chloride is acidic in nature? Illustrate your answer with the help of a chemical equation.

Answer 1

The chemical formula of ammonium chloride is $N{H}_{4}Cl$. Since, ammonium chloride is the salt of a strong acid $HCl$ and a weak base $N{H}_{4}OH$, so an aqueous solution of ammonium chloride is acidic in nature.

When dissolved in water, it gets hydrolysed to some extent to form $HCl$ and $N{H}_{4}OH$. $HCl$ being a strong acid is fully ionised and gives a large amount of hydrogen ions whereas $N{H}_{4}OH$ is only slightly ionised.

So, $N{H}_{4}Cl$ contains more of hydrogen ions than hydroxide ions and is hence acidic in nature.

$N{H}_{4}Cl\left(s\right)+H_{2}O\left(l\right)\stackrel{Hydrolysis}{\to }N{H}_{4}OH\left(aq\right)+HCl\left(aq\right)$