Title: Lead Chromate(VI)
CAS Registry Number: 7758-97-6
Additional Names: Chrome yellow; Cologne yellow; King's yellow; Leipzig yellow; Paris yellow; C.I. Pigment Yellow 34; C.I. 77600
Molecular Formula: CrO4Pb
Molecular Weight: 323.19
Percent Composition: Cr 16.09%, O 19.80%, Pb 64.11%
Line Formula: PbCrO4
Literature References: Occurs in nature as the minerals crocoite, phoenicochroite. Ref: Colour Index vol. 4 (3rd ed., 1971) p 4677. Evaluation of carcinogenic risk: IARC Monographs 23, 205-324 (1980); ibid. 49, 49-256 (1990). Review of environmental exposure and bioavailability: D. Waldron, Am. Ink Maker 72, 50-60 (1994); of toxicology and human exposure: Toxicological Profile for Lead (PB99-166704, 1999) 640 pp.
Properties: Yellow or orange-yellow powder. d 6.3. mp 844°. It is one of the most insol salts (0.2 mg/l H2O). Insol in acetic acid. Sol in solns of fixed alkali hydroxides, in dil HNO3.
Melting point: mp 844°
Density: d 6.3
CAUTION: Chromium hexavalent compounds are listed as known human carcinogens: Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-63.
Use: Pigment for paints and inks; in oil and water colors; printing fabrics, decorating china and porcelain; in chemical analysis of organic substances; in traffic paints. |