Also known as chloromagnestite, magnesium chloride is a colorless crystalline solid. It is very hygroscopic in nature. It is soluble in water and alcohol. It can be prepared by heating hydrated magnesium chloride crystals in a current of dry hydrogen chloride or by heating magnesium ammonium chloride. Anhydrous magnesium chloride crystallizes from magnesium chloride hexahydrate as leaflets. It is electrically conductive. The crystal structure of MgCl2 is layer like. The structure is cubic close packing with alternate layers of octahedral holes occupied by Mg2+ ions.