Lead is only slightly attacked by dilute hydrochloric acid, because a protective coating of $\mathrm{P}\mathrm{b}\mathrm{C}{\mathrm{l}}_2$ is formed on the Pb surface which prevents the further reaction. Powdered lead is readily dissolved by boiling HCl, due to the formation of the soluble complex, ${\mathrm{H}}_2\left[\mathrm{P}\mathrm{b}\mathrm{C}{\mathrm{l}}_4\right]$ .
$\mathrm{P}\mathrm{b}+\mathrm{H}\mathrm{C}\mathrm{l}\stackrel{\mathrm{B}\mathrm{o}\mathrm{i}\mathrm{l}\mathrm{i}\mathrm{n}\mathrm{g}}{\to }\mathrm{P}\mathrm{b}\mathrm{C}{\mathrm{l}}_2+{\mathrm{H}}_2$
$\mathrm{P}\mathrm{b}\mathrm{C}{\mathrm{l}}_2+2\mathrm{H}\mathrm{C}\mathrm{l}\to \underset{\left(\mathrm{C}\mathrm{h}\mathrm{l}\mathrm{o}\mathrm{r}\mathrm{o}\mathrm{p}\mathrm{l}\mathrm{u}\mathrm{m}\mathrm{b}\mathrm{i}\mathrm{c}\mathrm{a}\mathrm{c}\mathrm{i}\mathrm{d}\right)}{{\mathrm{H}}_2\left[\mathrm{P}\mathrm{b}\mathrm{C}{\mathrm{l}}_4\right]}$