Title: Sodium Tungstate(VI)
CAS Registry Number: 13472-45-2
CAS Name: (
T-4)-Disodium tungstate (WO42-)
Molecular Formula: Na2O4W
Molecular Weight: 293.82
Percent Composition: Na 15.65%, O 21.78%, W 62.57%
Line Formula: Na2WO4
Literature References: Crystals have a spinel structure isomorphous with sodium molybdate(VI),
q.v. Mfr: N. T. Gordon, A. F. Spring,
Ind. Eng. Chem. 16, 555 (1924). Properties of sodium tungstate derivatives: E. F. Smith,
J. Am. Chem. Soc. 44, 2027 (1922). Crystal structure: I. Lindqvist,
Acta Chem. Scand. 4, 1066 (1950). Polymerization study: M. L. Freedman,
J. Am. Chem. Soc. 80, 2072 (1958). Thermochemistry study: R. L. Graham, L. G. Hepler,
ibid. 3538. HPLC and CZE analysis: K. Hettiarachchi
et al., J. Pharm. Biomed. Anal. 13, 515 (1995). Pharmacokinetics in rats: S. Le Lamer-Déchamps
et al., Int. J. Pharm. 248, 131 (2002). Antidiabetic effects in rats: A. Barberà
et al., Diabetologia 44, 507 (2001). Review of toxicity: B. Venugopal, T. D. Luckey,
Environ. Qual. Safety, Suppl. 1, 4-73 (1975); of toxicology and human exposure:
Toxicological Profile for Tungsten (PB2006-100007, 2005) 203 pp.
Derivative Type: Dihydrate
CAS Registry Number: 10213-10-2
Properties: Colorless crystals or white, cryst powder, mp 665°. Effloresces in dry air. Loses its water at 100°. Sol in about 1.1 parts water. Insol in alcohol. The aq soln is slightly alkaline, pH 8-9. LD50 (mg tungstate/kg) in rabbits: 105 i.m.; in rats: 240 s.c. (Venugopal, Luckey).
Melting point: mp 665°
Toxicity data: LD50 (mg tungstate/kg) in rabbits: 105 i.m.; in rats: 240 s.c. (Venugopal, Luckey)
Use: Fireproofing and waterproofing fabrics; preparing complex compds such as phosphotungstate and silicotungstate; as a protective colloid in biological development methods; precipitant for alkaloids; catalyst in oxidation reactions; corrosion inhibitor for steel.
