Title: Chromic Sulfate
CAS Registry Number: 10101-53-8
CAS Name: Sulfuric acid chromium(3+) salt (3:2)
Additional Names: chromium(III) sulfate
Molecular Formula: Cr2O12S3
Molecular Weight: 392.18
Percent Composition: Cr 26.52%, O 48.96%, S 24.53%
Line Formula: Cr2(SO4)3
Literature References: Prepn of anhydr salt by dehydration of hydrated forms: Rollinson, Bailar, Jr., Inorg. Synth. 2, 197 (1946). Toxicity data: Cavalli, Arch. Int. Pharmacodyn. 62, 330 (1939).
Properties: Peach-colored solid. d 3.012. Practically insol in water and acids. MLD in frogs, mice, rabbits (mg/kg): 37, 246.8, 215 i.v. (Cavalli).
Density: d 3.012
Toxicity data: MLD in frogs, mice, rabbits (mg/kg): 37, 246.8, 215 i.v. (Cavalli)
Derivative Type: Hydrates
Properties: Are known in both green and violet modifications, and have several degrees of hydration up to 18H2O: Lukaszewski, Redfern, Nature 190, 805 (1961); Udy in Chromium vol. 1, M. J. Udy, Ed., A.C.S. Monograph Series no. 132 (Reinhold, New York, 1956) pp 213-217, 288. The technical product comes in the form of a finely granular, dark-green flake or powder approximating the formula Cr2(SO4)3.10H2O. Readily sol in water. Almost insol in alc.
Derivative Type: Basic chromic sulfates
Properties: Of the type Cr(OH)SO4.nH2O are of importance in the tanning industry: Udy, loc. cit. and pp 278-280, 305-308. Technical grades are available in two degrees of basicity, one-third and one-half, as finely granular dark-green flakes or powder contg about 25% Cr2O3. Readily sol in water.
Use: Insolubilization of gelatin; in catalyst prepn; as mordant in textile industry; in tanning of leather; in chrome plating; in manuf of Cr, CrO3, and Cr alloys; to improve dispersibility of vinyl polymers in water; in manuf of green varnishes, paints, inks, glazes for porcelain. |