Question : Aqueous solutions of sodium chloride, sodium sulphate and calcium chloride are taken in three separate test tubes. Using aqueous barium chloride how do you identify sodium sulphate?

Question : Aqueous solutions of sodium chloride, sodium sulphate and c

1.	Question : Aqueous solutions of sodium chloride, sodium sulphate and calcium chloride are taken in three separate test tubes. Using aqueous barium chloride how do you identify sodium sulphate?
Answer» Solution :When a solution of sodium sulphate is added to a solution of barium chloride a white precipitate of barium sulphate will be formed IMMEDIATELY. This precipitate is insoluble in dil-Hydrochloric acid and also insoluble in water. This type of reaction is called precipitation reaction as the `BaSO_4`precipitate THUS formed is of white COLOUR. `Na_2 SO_4 (aq) + BaCl_2 (aq) to BaSO_4(s) + 2NaCl(aq)` Since, barium sulphate is insoluble in water. So it will precipitate as a SOLID, WHEREAS the sodium chloride will remain in solution.