A solution reacts with crushed eggshells to give a gas that turns lime-water milky. What does the solution contain?

A solution reacts with crushed egg shells to give a gas that turns lime-water milky. The solution contains $\mathit{HCl}$.

Eggshells are composed of calcium carbonate. When eggshells are subjected to $\mathit{HCl}$ acid, $\mathit{CaC}{O}_3$ reacts with hydrochloric acid to liberate carbon dioxide gas. The carbon dioxide gas that is liberated turns the lime-water milky. The reactions are given as:-
$\mathit{CaC}{O}_3+2\mathit{HCl }\to \mathit{ CaC}{l}_2+H_{2}O+C{O}_2$
$\mathit{Ca}{\left(\mathit{OH}\right)}_2+C{O}_2\to \mathit{CaC}{O}_3+H_{2}O$