Title: Sodium Trimetaphosphate
CAS Registry Number: 7785-84-4
CAS Name: Metaphosphoric acid trisodium salt
Molecular Formula: Na3O9P3
Molecular Weight: 305.89
Percent Composition: Na 22.55%, O 47.07%, P 30.38%
Line Formula: (NaPO3)3
Literature References: Prepd by tempering sodium hexametaphosphate at about 500° for 8-12 hrs; by heating Na2HPO4 and NH4NO3 to 320° or by heating NaH2PO4 at 530°: Fleitmann, Henneberg,
Ann. 65, 304 (1848); v. Knoore,
Z. Anorg. Allg. Chem. 24, 381 (1900); Karbe, Jander,
Kolloid-Beih. 54, 35 (1942); Bell,
Inorg. Synth. 3, 103 (1950); Lee, Bond,
J. Appl. Chem. 18, 345 (1968). Crystal structure of hexahydrate: Caglioti
et al., Atti Acad. Italia Rend. 3 [7], 761 (1942),
C.A. 40, 6927b (1946); of anhydrate: Ondik,
Acta Crystallogr. 18, 226 (1965). Use in detergent processing: Shen,
J. Am. Oil Chem. Soc. 45, 510 (1968). Toxicity study: Behrens, Seelkopf,
Arch. Exp. Pathol. Pharmakol. 169, 238 (1932).
Reviews: see Sodium Metaphosphate.
Derivative Type: Hexahydrate
Properties: Efflorescent, triclinic-rhombohedral prisms. d 1.786. mp 53°. Loses water on storage at 20°, becomes definitely anhydr at 100°. d (anhydr) 2.49. One gram dissolves in 4.5 ml water. Insol in alc. LD orally in mice: >100 mg/kg (Behrens, Seelkopf).
Melting point: mp 53°
Density: d 1.786; d (anhydr) 2.49
Toxicity data: LD orally in mice: >100 mg/kg (Behrens, Seelkopf)
Use: In detergent processing.