For each of the following precipitation reactions, complete and balance the equation, indicating clearly which product is the precipitate. a) Ba(NO3)2(aq) + (NH4)2SO4(aq)
b)CoCl3(aq) + NaOH(aq)
c)FeCl3(aq) + (NH4)2SS(aq)

a) Ba(NO₃)₂(aq) + (NH₄)₂SO₄(aq) ⇒ 2 NH₄NO₃(aq) + BaSO₄(s)

b) CoCl₃(aq) + 3 NaOH(aq) ⇒ 3 NaCl(aq) + Co(OH)₃(s)

c) 2 FeCl₃(aq) + 3 (NH₄)₂S(aq) ⇒ 6 NH₄Cl(aq) + Fe₂S₃(s)

Explanation:

We have 3 double displacement reactions, in which both reactants exchange their cations and anions, and an insoluble compound is formed and precipitates as a solid. This is indicated as (s).

a) Ba(NO₃)₂(aq) + (NH₄)₂SO₄(aq) ⇒ 2 NH₄NO₃(aq) + BaSO₄(s)

b) CoCl₃(aq) + 3 NaOH(aq) ⇒ 3 NaCl(aq) + Co(OH)₃(s)

c) 2 FeCl₃(aq) + 3 (NH₄)₂S(aq) ⇒ 6 NH₄Cl(aq) + Fe₂S₃(s)