Copper chloride. Copper ions will form precipitated with sulfide, Coppersulfide. For other cations, there are solubile when there form with eithersulfide ions or acetate ions. So, the only way to separate is using copper ions. Solution Copper chloride. Copper ions will form precipitated with sulfide, Coppersulfide. For other cations, there are solubile when there form with eithersulfide ions or acetate ions. So, the only way to separate is using copper ions..