zinkchloride

Zinc chloride (ZnCl2) is an inorganic compound that forms a white, crystalline solid. The anhydrous material is highly hygroscopic and readily absorbs moisture from the air. It dissolves easily in water and forms various hydrates, with properties that change in the presence of water and chloride ligands.

In aqueous solution ZnCl2 undergoes hydrolysis, producing zinc hydroxide and hydrochloric acid, and the solution can contain chloro-complexes such as [ZnCl3]− and [ZnCl4]2−. The compound is a Lewis acid and commonly acts as a dehydrating and coordinating species in catalytic and organic synthesis contexts.

Production and occurrence: ZnCl2 is produced industrially by direct chlorination of zinc metal or by reacting zinc oxide with hydrochloric acid. It occurs in nature only rarely as minerals such as simonkolleite (Zn5(OH)2Cl2·H2O), reflecting its primarily synthetic nature.

Uses: It is widely used as a flux in soldering and brazing, in organic synthesis as a Lewis acid catalyst, and as a drying or dehydrating agent. It also has applications in textile processing and metal finishing, where its hygroscopic and coordinating properties are advantageous.

Safety and handling: Zinc chloride is corrosive and irritant to skin, eyes, and the respiratory tract. It should be handled with appropriate personal protective equipment, and kept away from moisture and incompatible materials. In case of spillage, it should be contained and cleaned up with suitable absorbents and disposed of according to local regulations.