In the qualitative analysis scheme for metal ions,how are the Analytical Group III cations separated from the cations of Analytical Groups IV and V? A)by addition of HCl,forming insoluble metal chlorides B)by addition of H₂SO₄,forming insoluble metal sulfates C)by addition of H₂S in acidic solution,forming insoluble metal sulfides D)by addition of H₂S in basic solution,forming insoluble metal sulfides or hydroxides E)by addition of (NH₄)₂CO₃ or (NH₄)₃PO₄,forming insoluble metal carbonates or phosphates

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Analytical Group III cations (Al³⁺, Cr³⁺, Fe³⁺, Co²⁺, Ni²⁺, Mn²⁺, and Zn²⁺) are separated from the cations of Analytical Groups IV and V by adding H₂S in basic solution. This forms insoluble metal sulfides or hydroxides. The sulfides or hydroxides of Group III cations are insoluble in ammonium hydroxide solution but dissolve in mineral acids. On the other hand, the cations of Analytical Groups IV and V are not precipitated in basic solution and require a different method of separation.

In the Qualitative Analysis Scheme for Metal Ions,how Are the Analytical