## Chemistry: The Molecular Science (5th Edition)

Acid and base used to form this ion, respectively, : $H_2SO_4$ and $Ca(OH)_2$, Complete ionic equation: $H^+(aq) + HS{O_4}^{-}(aq) + Ca^{2+}(aq) + 2OH^-(aq) -- \gt CaSO_4(s) + 2H_2O(l)$ Net ionic equation: $H^+(aq) + HS{O_4}^{-}(aq) + Ca^{2+}(aq) + 2OH^-(aq) -- \gt CaSO_4(s) + 2H_2O(l)$
1. Identify the ions of the salt: $(NaNO_2)$: $Ca^{2+}$ and $S{O_4}^{2-}$: To the cation, add hydroxide ions: $Ca(OH)_2$; this is the base. To the anion, add hydrogen ions: $H_2SO_4$; this is the acid. 2. Now, write the balanced overall equation between, which is: $Acid + Base -- \gt Salt + Water$ We already have the salt, so: $H_2S{O_4}(aq) + Ca(OH)_2(aq) -- \gt CaSO_4(s) + H_2O(l)$ ** Acording to table 3.1, $CaSO_4$ is not soluble in water. 3. Write the complete ionic equation. - For the completely dissociated/ionized compounds, separate them by their ions: $H^+(aq) + HS{O_4}^{-}(aq) + Ca^{2+}(aq) + OH^-(aq) -- \gt CaSO_4(s) + H_2O(l)$ * $H_2SO_4$ is a strong acid, but only for one of its hydrogens; therefore, it is totally dissociated in $H^+$ and $HS{O_4}^-$. * $Ca(OH)_2$ is a strong base, so it is completely ionized in water. Balance it: $H^+(aq) + HS{O_4}^{-}(aq) + Ca^{2+}(aq) + 2OH^-(aq) -- \gt CaSO_4(s) + 2H_2O(l)$ 4. Remove the repeated ions: $H^+(aq) + HS{O_4}^{-}(aq) + Ca^{2+}(aq) + 2OH^-(aq) -- \gt CaSO_4(s) + 2H_2O(l)$ This is the net ionic equation.