CdCl2

Cadmium chloride, or cadmium dichloride, is an inorganic compound with the formula CdCl2. It appears as a white crystalline solid that is highly hygroscopic, readily absorbing moisture from the air. It is soluble in water, producing an aqueous solution containing Cd2+ and Cl−. The compound commonly forms hydrates, with the dihydrate CdCl2·2H2O being a frequently encountered form when exposed to moisture.

CdCl2 can be prepared by several methods. It is typically produced by reacting cadmium metal or cadmium oxide with hydrochloric acid, or by chlorinating cadmium compounds using chlorine gas. In industry, the anhydrous salt or its hydrates are produced for use as reagents.

In aqueous solution, CdCl2 dissociates to cadmium and chloride ions. In high chloride concentrations, cadmium can form various chloro complexes, reflecting the coordination chemistry of Cd2+ in halide-rich media. CdCl2 is a versatile precursor for the synthesis of other cadmium compounds, notably cadmium sulfide (CdS) pigments, and for preparing cadmium salts used in electronics and materials synthesis. It is also employed in laboratory settings as a reagent and as a source of Cd2+ in coordination chemistry studies.

Safety and environmental considerations are important. Cadmium chloride is toxic, and cadmium compounds are associated with carcinogenic and kidney-damaging effects. Exposure can occur via inhalation, ingestion, or skin contact; proper handling, engineering controls, and personal protective equipment are required. Waste containing cadmium compounds is regulated and must be disposed of as hazardous waste in accordance with applicable guidelines.