Nomenclature
CAS number: 10025-73-7
Cl
3Cr; mol wt 158.36.
Cl 67.16%, Cr 32.83%.
CrCl
3.
Description and references
Prepn: Heisig et al., Inorg. Synth. 2, 193 (1946); Pray, ibid. 5, 153 (1953); Vavoulis et al., ibid. 6, 129 (1960); Hein, Herzog in Handbook of
Preparative Inorganic Chemistry vol. 2, G.
Brauer, Ed. (Academic Press, New York, 2nd ed., 1965) pp 1338-1340;
prepn of hexahydrates: eidem, ibid. pp 1348-1350.
Toxicity data: Cavalli, Arch. Int. Pharmacodyn. 62, 330 (1939).
Properties
Violet, lustrous, hexagonal, cryst scales. Greasy
feel. mp 1152°;
dissociates above 1300°. d25 2.87. The rate of soln in water, acids, organic
solvents is extremely slow. Addition of a trace of CrCl2 or wetting agent aid in rapid soln in water, alcohol. Also exists
in hygroscopic, sol, peach-blossom colored form. Keep tightly closed. MLD in frogs,
mice, rabbits (mg/kg): 187, 801, 288 i.v. (Cavalli).Derivative
Hexahydrates.
Properties
Several known isomers. Dichlorotetraaquochromium chloride dihydrate, [trans-[CrCl2(H2O)4]Cl.2H2O]; dark green salt, monoclinic crystals; d 1.849: Freeman, Dance, Inorg. Chem. 4, 1555 (1965); Morosin, Acta Crystallogr. 21, 280 (1966). Hexaaquochromium trichloride, [[Cr(H2O)6]Cl3]; violet,
rhombohedral hydrate. Chloropentaaquochromium dichloride monohydrate, [[CrCl(H2O)5]Cl2.H2O]; light green isomer. All are deliquesc in air. Sol in
water; dil aq solns are violet, concd aq solns are green. pH of 0.2
molar aq soln 2.4. Sol in alcohol; slightly sol in acetone. Practically
insol in ether. Keep well closed.Use
In chromizing; manuf of Cr metal and compds; as
catalyst for polymerization of olefins and other organic reactions;
as textile mordant; in tanning; in corrosion inhibitors; as waterproofing
agent.