Title: Phosphorus Trioxide
CAS Registry Number: 1314-24-5
Additional Names: Diphosphorus trioxide
Molecular Formula: O3P2
Molecular Weight: 109.95
Percent Composition: O 43.65%, P 56.34%
Line Formula: P2O3
Literature References: Exists as P4O6. Prepd by treating PCl3 with tetramethylammonium sulfite in liq SO2: Jander et al., Ber. 77, 689 (1944). Alternate prepn from the elements: Thorpe, Tutton, J. Chem. Soc. 57, 545 (1890); Miller, ibid. 1928, 1847; 1929, 1823; Wolf, Schmager, Ber. 62, 779 (1929). Chemistry: Riess, Van Wazer, Inorg. Chem. 5, 178 (1966).
Properties: Transparent monoclinic crystals or colorless liquid. Very poisonous! d421 2.135. mp 23.8°. bp 173.1° in nitrogen atm. Disproportionates into red P and P2O4 when heated above 210°. Sol in benzene, carbon disulfide. When placed in cold water, H3PO3 is formed slowly. Hot water produces a violent reaction with the formation of red phosphorus, phosphine, and H3PO4.
Melting point: mp 23.8°
Boiling point: bp 173.1° in nitrogen atm
Density: d421 2.135 |