Predicting Precipitation Reactions

Example on Predicting Precipitation Reactions

Predict the result of mixing reasonably concentrated solutions of the following ionic compounds. If precipitation is expected, write a balanced net ionic equation for the reaction.

(a) potassium sulfate and barium nitrate
(b) lithium chloride and silver acetate
(c) lead nitrate and ammonium carbonate

Solution

(a) The two possible products for this combination are KNO₃ and BaSO₄. The solubility guidelines indicate BaSO₄ is insoluble, and so a precipitation reaction is expected. The net ionic equation for this reaction, derived in the manner detailed in the previous module, is

\(\mathrm{Ba^{2+}}(aq) + \mathrm{SO_4^{2−}}(aq) \longrightarrow \mathrm{BaSO_4}(s)\)

(b) The two possible products for this combination are LiC₂H₃O₂ and AgCl. The solubility guidelines indicate AgCl is insoluble, and so a precipitation reaction is expected. The net ionic equation for this reaction, derived in the manner detailed in the previous module, is

\(\mathrm{Ag^{+}}(aq) + \mathrm{Cl^{−}}(aq) \longrightarrow \mathrm{AgCl}(s)\)

(c) The two possible products for this combination are PbCO₃ and NH₄NO₃. The solubility guidelines indicate PbCO₃ is insoluble, and so a precipitation reaction is expected. The net ionic equation for this reaction, derived in the manner detailed in the previous module, is

\(\mathrm{Pb^{2+}}(aq) + \mathrm{CO_3^{2−}}(aq) \longrightarrow \mathrm{PbCO_3}(s)\)