in the reaction BaCI2 (aq) + Na2So4 (aq) BaSO4 (s) + 2NaCI (aq) what phase are the reactants in before reaction? 1.BaCI2 is a solid and Na2SO4 is in aqueous solution 2.both reactants are gases 3.BaCI2 is a liquid and Na2SO4 is a gas 4. Both reactants are in aqueous solution