## Chemistry and Chemical Reactivity (9th Edition)

$X^{m-}$ is the anion released by the ionization of the acid. First reaction: $m/2\ Na_2S(aq)+H_mX(aq)\rightarrow m/2\ H_2S(g)+Na_mX(aq)$ Net ionic equation: $S^{2-}(aq)+2\ H_3O^+(aq)\rightarrow H_2S(g)+2\ H_2O(l)$ Second reaction: $H_2S(g)+Pb(NO_3)_2(aq)\rightarrow 2\ HNO_3(aq)+ PbS(s)$ Net ionic equation: $2\ H_2O(l)+H_2S(g)+Pb^{2+}(aq)\rightarrow 2\ H_3O^+(aq)+ PbS(s)$