Aluminium Chloride

AlCl,. If aluminium hydroxide be treated with hydrochloric acid, aluminium chloride is formed, and crystallizes from the solution as AlCl,.6H,O. If the attempt be made to drive off the water of crystallization, the compound is decomposed, leaving alumina as a residue. To make anhydrous aluminium chloride, chlorine is pa ed over a heated mixture of the oxide and carbon. The chloride is volatile and is deposited in the cool part of the apparatus. When exposed to the air it attracts moisture. Aluminium chloride boils at 180° C. With sodium chloride and pota ium chloride it forms double salts of the composition AlCl. NaCl and AlCl, KCI.