Phosphorus trioxide

Phosphorus(III) oxide
Ball-and-stick model of the P4O6 molecule
Phosphorus in orange, oxygen in red
Packing of P4O6 molecules in the crystal structure
Names
IUPAC names
Tetraphosphorus hexaoxide
Tricyclo[3.3.1.13,7]tetraphosphoxane
Systematic IUPAC name
2,4,6,8,9,10-Hexaoxa-1,3,5,7-tetraphosphatricyclo[3.3.1.13,7]decane
Other names
Phosphorus sesquioxide
Phosphorous anhydride
Tetraphosphorous hexoxide
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.032.414 Edit this at Wikidata
EC Number
  • 235-670-5
26856
UNII
  • InChI=1S/O6P4/c1-7-2-9-4-8(1)5-10(3-7)6-9 checkY
    Key: VSAISIQCTGDGPU-UHFFFAOYSA-N checkY
  • InChI=1/O6P4/c1-7-2-9-4-8(1)5-10(3-7)6-9
    Key: VSAISIQCTGDGPU-UHFFFAOYAV
  • O1P3OP2OP(OP1O2)O3
Properties
P4O6
Molar mass 219.88 g mol−1
Appearance colourless monoclinic crystals or liquid
Density 2.135 g/cm3
Melting point 23.8 °C (74.8 °F; 296.9 K)
Boiling point 173.1 °C (343.6 °F; 446.2 K)
reacts
Acidity (pKa) 9.4
Structure
See Text
0
Hazards
GHS labelling:
GHS06: Toxic
Danger
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
0
0
Related compounds
Other anions
 Phosphorus trisulfide
Other cations
 Dinitrogen trioxide
Arsenic trioxide
Antimony trioxide
Related compounds
 Phosphorus pentoxide
Phosphorous acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Phosphorus trioxide is the chemical compound with the molecular formula P4O6. Although the molecular formula suggests the name tetraphosphorus hexoxide, the name phosphorus trioxide preceded the knowledge of the compound's molecular structure, and its usage continues today. This colorless solid is structurally related to adamantane. It is formally the anhydride of phosphorous acid, H3PO3, but cannot be obtained by the dehydration of the acid. A white solid that melts at room temperature, it is waxy, crystalline and highly toxic, with garlic odor.[1]

  1. ^ A. F. Holleman; Wiberg, Egon; Wiberg, Nils (2001). Inorganic Chemistry. Boston: Academic Press. ISBN 0-12-352651-5.