Cadmium(II) hydroxide is prepared by dissolving 3 g of cadmium(II) nitrate in 10 mL of water, where to a solution prepared from 0.78 g of NaOH in 10 mL of water is added with stirring. The mixture is acidified with conc. hydrochloric acid in order to prepare cadmium(II) chloride, whereto a solution prepared from 0.7 g of sodium sulfide in 5 mL of water is added with stirring. The mixture is filtered, washed with water and dried in open air.
Cd(NO3)2 + 2 NaOH = Cd(OH)2 + 2 NaNO3
Cd(OH)2 + 2 HCl = CdCl2 + 2 H2O
CdCl2 + Na2S = CdS + 2 NaCl
Addition of the NaOH
Addition of the HCl
Addition of the Na2S
The dry product