Barium chloride solution reacts with sodium sulfate solution to form a white precipitate. What is the chemical formula of the precipitate?
Correct: B
This is a double displacement reaction where ions are exchanged:
BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq)
Barium sulfate (BaSO₄) is insoluble in water, and therefore it forms a white precipitate. Sodium chloride (NaCl) remains dissolved in the aqueous solution.