염화 코발트

Cobalt chloride (CoCl₂) is a purplish-red or red monoclinic crystal that is slightly weathered and easily deliquescent. It has a melting point of 724°C and is soluble in water, ethanol, ether, and acetone. The anhydrous compound has the molecular formula CoCl₂, containing 45.4% cobalt and 54.6% chlorine. The monohydrate compound has the molecular formula CoCl₂·H₂O, containing 39.9% cobalt. The hexahydrate compound has the molecular formula CoCl₂·6H₂O, containing 24.8% cobalt. Cobalt chloride crystals are stable at room temperature but lose water of crystallization and turn blue when heated. They turn red in humid air. When heated or when concentrated hydrochloric acid, chloride, or organic solvents are added, its aqueous solution becomes blue. The compound crystallizes at 30–45°C and begins to weather, becoming turbid. It forms a tetrahydrate when heated at 45–50°C for 4 hours, and becomes anhydrous when heated to 110°C. It is obtained through the reaction of cobalt powder, cobalt oxide, cobalt hydroxide, or cobalt carbonate with hydrochloric acid.

정의ChEBI: Cobalt dichloride is a cobalt salt in which the cobalt metal is in the +2 oxidation state and the counter-anion is chloride. It is used as an indicator for water in desiccants. It has a role as a two-colour indicator, an allergen, a calcium channel blocker and a sensitiser. It is a cobalt salt and an inorganic chloride. It contains a cobalt(2+).