Write the formula unit equation for this reaction occurring in water: Potassium sulfate and barium chloride are mixed to form potassium chloride and barium sulfate.
1. K₂SO₄ (s) + BaCl₂ (s) → 2 KCl (aq) + BaSO₄ (s)
2. K₂SO₄ (aq) + BaCl₂ (aq) → 2 KCl (aq) + BaSO₄ (s)
3. 2 K₃SO4 (aq) + 3 BaCl₂ (aq) → 6 KCl (aq) + 2 Ba₃(SO₄)₂ (s)
