Chromous Chloride

Title: Chromous Chloride
CAS Registry Number: 10049-05-5
Molecular Formula: Cl2Cr
Molecular Weight: 122.90
Percent Composition: Cl 57.69%, Cr 42.31%
Line Formula: CrCl2
Literature References: Prepn: Burg, Inorg. Synth. 3, 150 (1950); Hein, Herzog, in Handbook of Preparative Inorganic Chemistry Vol. 2, G. Brauer, Ed. (Academic Press, New York, 2nd ed. 1965) pp 1336-1338. Prepn of tetrahydrate: Balthis, Jr., Bailar, Jr., Inorg. Synth. 1, 125 (1939); Holah, Fackler, ibid. 10, 26 (1967). Toxicity study: H. F. Smyth et al., Am. Ind. Hyg. Assoc. J. 30, 470 (1969).
Properties: Lustrous needles or fused, fibrous mass. mp 824°; d414 2.751. Very hygroscopic; stable in dry air but oxidizes rapidly if moist. Powerful reducing agent. Soluble in water giving a blue soln. Keep well closed. LD50 orally in rats: 1.87 g/kg (Smyth).
Melting point: mp 824°
Density: d414 2.751
Toxicity data: LD50 orally in rats: 1.87 g/kg (Smyth)
Derivative Type: Tetrahydrate
Additional Names: Tetraaquochromium dichloride
Properties: Bright blue, hygroscopic crystals. Above 38° changes to isomeric green modification. Loses 1H2O, forming trihydrate, at 51°. Absorbs O2 even when dry, forming a greenish-black oxychloride. Sol in water. Almost insol in concd HCl. On standing in soln it is oxidized by the water with liberation of H2. Keep well closed.
Use: In chromizing; in prepn of Cr metal; in catalysts for organic reactions; as O2 absorbent; in analysis.
Chromous Fluoride Chromous Formate Chromous Oxalate Chromous Sulfate Chromyl Chloride