Question

What happens when hcl gas is dissolved in water why it conducts electricity?

Answer 1

Well, heat evolves as the water hydrates the hydrogen chloride molecule, and your addition is safe.

Hydrogen chloride is a room temperature gas. Of course, it is very soluble in water to the extent of approx. 10 mol per litre under normal conditions. As a strong acid, in water, dissociation, and protonolysis is represented by the equation…

HCl(aq)+H2O→H3O++Cl−+ΔHCl(aq)+H2O→H3O++Cl−+Δ

This reaction, when we add acid to water is strongly exothermic (and the origin of the saying when you spit in acid it spits back…and hence when we do such dilutions we ALWAYS ADD THE ACID TO WATER and never the reverse).

Note that we represent the acidium ion as H3O+H3O+, also known as the hydronium ion…it is a cluster of water molecules with an EXTRA H+H+, that we sometimes represent as simply H+H+.