Question

What happens when hydrogen chloride gas is dissolved in water?

Answer 1

Hydrogen chloride gas

• The gas hydrogen chloride $\left(\mathrm{HCl}\right)$ contains hydrogen and chlorine atoms.
• Due to the large electronegativity difference between hydrogen and chlorine, it is considered a polar compound.
• Its polar nature makes it water-soluble.

Hydrogen chloride gas dissolved in water

• When hydrogen chloride gas is dissolved in water, an acidic solution is formed due to the generation of hydronium $\left({\mathrm{H}}_3{\mathrm{O}}^{+}\right)$ ions.
• The reaction is as follows:
• $\underset{\left(\mathrm{Hydrochloric}\mathrm{acid}\right)}{\mathrm{HCl}\left(\mathrm{aq}\right)}+\underset{\left(\mathrm{Water}\right)}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\left(\mathrm{Hydronium}\mathrm{ion}\right)}{{\mathrm{H}}_3{\mathrm{O}}^{+}\left(\mathrm{aq}\right)}+\underset{\left(\mathrm{Chloride}\mathrm{ion}\right)}{{\mathrm{Cl}}^{-}\left(\mathrm{aq}\right)}$