chemical property

Teal rhombic crystals. Relative density 2.54. It is prone to deliquescence in humid air and weathering in dry air. Due to the ionic polarization and the Jahn–Teller effect, it has a plane square structure, unlike other transition metal dichlorides (such as Iron(II) chloride), which has a regular tetrahedron structure. Easily soluble in water, soluble in alcohol, ammonia, and acetone. It is also soluble in ether and ethyl acetate, so it is a commonly used catalyst in Organic reaction (especially hydrocarbon activation reaction). Its aqueous solution is weakly acidic. When heated to 100 ℃, two Water of crystallization are lost, but it is easy to hydrolyze at high temperature and it is difficult to obtain anhydrous salt. When crystallization is generated from Copper(II) chloride aqueous solution, dihydrate is obtained at 26~42 ℃, tetrahydrate is obtained below 15 ℃, trihydrate is obtained at 15~25.7 ℃, monohydrate is obtained above 42 ℃, and Anhydrous is obtained at 100 ℃.