Oxygen difluoride
1692055
203843838
2008-04-06T21:53:47Z
84.13.138.5
{{Chembox new
| Name = Oxygen difluoride
| ImageFile = Oxygen-difluoride-2D.png
| ImageSize = 160px
| ImageName = Structure and dimensions of the oxygen difluoride molecule
| ImageFile1 = Oxygen-difluoride-3D-vdW.png
| ImageSize1 = 160px
| ImageName1 = Space-filling model of the oxygen difluoride molecule
| OtherNames = difluorine monoxide<br />fluorine monoxide<br />oxygen difluoride<br />oxygen fluoride<br />hypofluorous anhydride
| Section1 = {{Chembox Identifiers
| CASOther = [7783-41-7]
}}
| Section2 = {{Chembox Properties
| Formula = OF<sub>2</sub>
| MolarMass = 53.9962 g mol<sup>−1</sup>
| Solvent = other solvents
| SolubleOther = 68 mL gaseous OF<sub>2</sub> in 1 L (0 °C)<ref>Yost, D. M. "Oxygen Fluoride" Inorganic Syntheses, 1939 volume, 1, pages 109-111.</ref>
| MeltingPt = −224 °C
| BoilingPt = −145 °C
}}
| Section4 = {{Chembox Thermochemistry
| DeltaHf = 24.5 kJ mol<sup>−1</sup>
}}
| Section8 = {{Chembox Related
| OtherCpds = [[Dioxygen difluoride|O<sub>2</sub>F<sub>2</sub>]]<br />[[difluoramine|NHF<sub>2</sub>]]<br />[[Nitrogen trifluoride|NF<sub>3</sub>]]<br />[[Sulfur dichloride|SCl<sub>2</sub>]]}}
}}
'''Oxygen difluoride''' is the [[chemical compound]] with the [[chemical formula|formula]] OF<sub>2</sub>. As predicted by [[VSEPR theory]], the molecule adopts a bent structure like [[water|H<sub>2</sub>O]], but it has very different properties, being a strong [[oxidizer|oxidant]].
==Preparation==
Oxygen difluoride was first reported in 1929; it was obtained by the electrolysis of molten [[potassium fluoride]] and [[hydrofluoric acid]] containing small quantities of [[Water (molecule)|water]].<ref>[[Paul Lebeau]]; Damiens, A. "A New Method for the Preparation of the Fluorine Oxide”<!--would be nice to get original titles in French-->Compt. rend. 1929, volume 188, 1253-5.</ref><ref>Lebeau, P.; Damiens, A. "The Existence of an Oxygen Compound of Fluorine"<!--would be nice to get original titles in French-->Compt. rend. 1927, volume 185, pages 652-4.</ref> The modern preparation entails the reaction of [[fluorine]] with a dilute aqueous solution of [[sodium hydroxide]]:
:2F<sub>2</sub> + 2NaOH → OF<sub>2</sub> + [[Sodium fluoride|2NaF]] + H<sub>2</sub>O
==Reactions==
Its powerful oxidizing properties are suggested by the [[oxidation number]] of +2 for the [[oxygen]] atom, which is unusual. Above 200 °C, OF<sub>2</sub> decomposes to oxygen and fluorine via a [[Radical (chemistry)|radical]] mechanism.
OF<sub>2</sub> reacts with many metals to yield [[oxide]]s and [[fluoride]]s. [[Nonmetal]]s also react: [[phosphorus]] reacts with OF<sub>2</sub> to form [[Phosphorus pentafluoride | PF<sub>5</sub>]] and POF<sub>3</sub>; [[sulfur]] gives [[sulfur dioxide|SO<sub>2</sub>]] and [[sulfur tetrafluoride|SF<sub>4</sub>]]; and unusually for a [[noble gas]], [[xenon]] reacts, yielding [[Xenon tetrafluoride|XeF<sub>4</sub>]] and xenon oxyfluorides.
Oxygen difluoride reacts very slowly with water to form [[hydrofluoric acid]]:
:OF<sub>2</sub>(aq) + H<sub>2</sub>O(aq) → 2HF(aq) + O<sub>2</sub>(g)
==Popular culture==
In [[Robert L. Forward]]'s [[science fiction]] novel ''[[Camelot 30K]]'', oxygen difluoride was used as a biochemical solvent by fictional life forms living in the solar system's [[Kuiper belt]].
==Safety==
OF<sub>2</sub> is a dangerous chemical, as is the case for any strongly oxidizing gas.
== References ==
{{Reflist}}
==External links==
* [http://www.npi.gov.au/database/substance-info/profiles/44.html National Pollutant Inventory - Fluoride and compounds fact sheet]
* [http://webbook.nist.gov/cgi/cbook.cgi?ID=C7783417 WebBook page for OF<sub>2</sub>]
[[Category:Oxygen compounds]]
[[Category:Fluorides]]
[[Category:Nonmetal halides]]
[[Category:Rocket oxidizers]]
[[bg:Кислороден дифлуорид]]
[[cs:Difluorid kyslíku]]
[[de:Sauerstoffdifluorid]]
[[pl:Difluorek tlenu]]
[[ru:Фторид кислорода(II)]]
[[zh:二氟化氧]]