試題詳解

3. A solution contains the ions Ag⁺, Pb²⁺, and Ni²⁺. Dilute solutions of NaCl, Na₂SO₄, and Na₂S are available to separate the positive ions from each other. In order to effect separation, the solutions should be added in which order?
(A)Na₂S, NaCl, Na₂SO₄
(B) Na₂SO₄, NaCl, Na₂S
(C) Na₂SO₄, Na₂S, NaCl
(D)NaCl, Na₂S, Na₂SO₄
(E) NaCl, Na₂SO₄, Na₂S