Qualitative Analysis of Cations This qualitative analysis applet involves cations of lead, silver, copper, iron, nickel, and mangenese, that can be classified in three groups: Group I: Pb2+, Ag+ Group II: Cu2+ Group III: Fe2+, Ni2+, Mn2+ In choosing your strategy for separating and identifying these cations, consider the following hints. 1. The Group I cations form insoluble chlorides. (Add a squirt of 6M HCl.) PbCl2(s) will dissolve in hot water. 2. Group II sulfides are insoluble in acidic solution. (Add a squirt of 6M HCl, a squirt of thioacetamide, and heat in the water bath.) 3. Group III sulfides are insoluble in basic solution. (Add another squirt of thioacetamide, heat, and then add concentrated ammonia.)