Aqueous solutions of both CoCl2 and the hydrate contain the species [Co(H2O)6]2+. They also contain chloride ions. In the solid state CoCl2•6H2O consists of the moleculetrans-[CoCl2(H2O)4] and two molecules of water of crystallization.[3] This species dissolves readily in water and alcohol. Concentrated aqueous solutions are red at room temperature but become blue when heated.[4] CoCl2•6H2O is deliquescent and the anhydrous salt CoCl2 is hygroscopic, readily converting to the hydrate.