Hexafluorophosphoric acid

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Hexafluorophosphoric acid[1]
Names
IUPAC name
Hydrogen hexafluorophosphate
Other names
Hexafluorophosphoric acid
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.037.263
EC Number 241-006-5
Properties
HPF6
Molar mass 145.972 g/mol
Appearance colorless oily liquid
Melting point decomposes at 25 °C
reacts
Hazards
Main hazards Corrosive
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Hexafluorophosphoric acid is the inorganic compound with the chemical formula H3OPF6. Although the formula is often written as HPF6, this compound is only available as the hydrate. This strong Brønsted acid features a non-coordinating anion, hexafluorophosphate (PF
6
). It is formed from the reaction of hydrogen fluoride with phosphorus pentafluoride.[2]

Like many strong acids, hexafluorophosphoric acid is not isolable but is handled only in solution. Its aqueous solutions consist of hydronium ion, H
3
O+
, and PF
6
. Additionally, such solutions often contain products derived from hydrolysis of the P-F bonds, including HPO
2
F
2
, H
2
PO
2
F
, and H
3
PO
4
, and their conjugate bases.[3] Hexafluorophosphoric acid attacks glass. Upon heating, it decomposes to generate HF. Crystalline HPF
6
has been obtained as the hexahydrate, wherein PF
6
is enclosed in truncated octahedral cages defined by the water and protons. NMR spectroscopy indicates that solutions derived from this hexahydrate contain significant amounts of HF.[3]

See also[edit]

References[edit]

  1. ^ Lide, David R. (1998). Handbook of Chemistry and Physics (87 ed.). Boca Raton, FL: CRC Press. pp. 4–74. ISBN 0-8493-0594-2. 
  2. ^ Arpad Molnar; G. K. Surya Prakash; Jean Sommer (2009). Superacid Chemistry (2nd ed.). Wiley-Interscience. p. 44. ISBN 0-471-59668-X. 
  3. ^ a b D. W. Davidson; S. K. Garg (May 1972). "The Hydrate of Hexafluorophosphoric Acid". Canadian Journal of Chemistry. 50: 3515–3520. doi:10.1139/v72-565.