Question

Which of the following would precipitate both the Be₂+ and Sr₂+ found in solution?

•С₂Н₃0₂-

•S₂-

•NO₃-

•Po₄3-

•So₄-

Answer 1

The ion that precipitates both Be₂⁺ and Sr₂⁺ from a solution is the phosphate ion, PO₄³⁺, forming beryllium phosphate and strontium phosphate.

Step-by-step explanation:

The ion that would precipitate both the Be₂⁺ and Sr₂⁺ found in a solution is the phosphate ion, PO₄³⁺. When these cations come into contact with phosphate ions, they form insoluble salts: beryllium phosphate (Be₃(PO₄)₂) and strontium phosphate (Sr₃(PO₄)₂), which precipitate out of the solution. The sulfate ion (SO₄²⁺) will precipitate only the Sr₂⁺ as strontium sulfate (SrSO₄), as beryllium sulfate (BeSO₄) is soluble. Neither acetate (C₂H₃O₂⁺), sulfide (S²⁺), nor nitrate (NO₃⁺) will precipitate both ions since they form soluble compounds with both Be₂⁺ and Sr₂⁺.