5662. Magnesium Chloride

Nomenclature

CAS number: 7786-30-3
Magnesium chloride (MgCl2); Magnogene.
Cl2Mg; mol wt 95.21.
Cl 74.47%, Mg 25.53%.
MgCl2.

Description and references

Prepd from magnesium ammonium chloride hexahydrate in the presence of HCl: Bryce-Smith, Inorg. Synth. 6, 9 (1960). Toxicity study: H. F. Smyth et al., Am. Ind. Hyg. Assoc. J. 30, 470 (1969).

Properties

Soft, highly deliquescent leaflets. mp 712° (rapid heating). d 2.41, also reported as d 2.325. Slow heating releases chlorine at 300°. Can be distilled in a stream of hydrogen. Attacks fused silica when melted. Sol in water, with the evolution of much heat, giving a clear soln. Easily forms alcoholates and etherates.

Derivative

Hexahydrate.

Nomenclature

CAS number: 7791-18-6
Cl2Mg.6H2O; mol wt 203.30.
Cl 34.88%, Mg 11.96%, H 5.95%, O 47.22%.

Properties

Deliquescent crystals. d 1.56. At 100° loses 2H2O (17.7%); at 110° begins to lose some HCl. By strong ignition is converted into oxychloride. mp, when rapidly heated, ≈118° with decompn. One gram dissolves in 0.6 ml water, 0.3 ml boiling water, 2 ml alcohol. Its aq soln is neutral. Keep well closed. LD50 orally in rats: 8.1 g/kg (Smyth).

Use

Fireproofing wood; in disinfectants; various magnesia cements; fire extinguishers; dressing cotton fabrics; in floor-sweeping compds; carbonizing wool; manuf parchment paper or artificial leather; as addition to casein glue. As a reagent in analytical chemistry for adjustment of ion strength.

Therapeutic Category

Cathartic.

Therapeutic Category (Veterinary)

Has been used in bovine hypomagnesemia.

Keywords

Laxative/Cathartic