Xenon tetrafluoride
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| Names | |||
|---|---|---|---|
| IUPAC name
Xenon tetrafluoride
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| Identifiers | |||
3D model (JSmol)
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| ECHA InfoCard | 100.033.858 | ||
PubChem CID
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CompTox Dashboard (EPA)
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| Properties | |||
| XeF4 | |||
| Molar mass | 207.2836 g mol−1 | ||
| Appearance | White solid | ||
| Density | 4.040 g cm−3, solid | ||
| Melting point | 117 °C (390 K)[1] | ||
| Structure | |||
| D4h | |||
| square planar | |||
| 0 D | |||
| Thermochemistry | |||
Std enthalpy of
formation (ΔfH⦵298) |
−284 kJ/mol[1] | ||
| Hazards | |||
| Flash point | ? °C | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Xenon tetrafluoride, XeF4, is one of the chemical compounds derived from the noble gas xenon. It was the first discovered noble gas compound containing a noble gas and exactly one other element.[2] It forms by the reaction of Xe and F2 in the ratio of 1 mol Xe to 2 mol F2.[3][4] The process is exothermic, releasing 251 kJ per mol of Xe.[2]
The structure was determined by NMR spectroscopy and x-ray crystallography in 1963.[5][6] The structure is square planar, as has been confirmed by neutron diffraction study,[7] and is justified by VSEPR theory because xenon has two lone pairs of electrons above and below the plane of the molecule.
Xenon tetrafluoride occurs as colorless crystals. It sublimes at 115.7 °C (240.26 °F).
Xenon fluorides are all exergonic and stable at normal temperatures. They react readily with water, even pulling water from air, so they must be kept in anhydrous conditions.
Synthesis
Xenon tetrafluoride is obtained by heating a mixture of xenon and fluorine with a 1:3 ratio in a nickel container to 400°C. Some xenon hexafluoride is also formed, which is increased with increasing fluorine concentration.[8]
Chemistry
Xenon tetrafluoride is hydrolysed by water to form elemental xenon, oxygen, hydrofluoric acid, and aqueous xenon trioxide.[9]
Reaction with tetramethylammonium fluoride forms tetramethylammonium pentafluoroxenate, which contains the pentagonal XeF−
5 anion.
It can also be oxidised by bismuth pentafluoride (BiF
5) to form the XeF+
3 cation:[10]
- BiF
5 + XeF
4 → XeF+
3BiF−
6
The XeF+
3 cation has also been identified in the salt [XeF+
3][Sb
2F−
11] by NMR spectroscopy.[11]
At 400°C, XeF
4 reacts with xenon gas to form XeF
2.[8]
Reaction with platinum metal yields platinum tetrafluoride and xenon gas.[8]
Applications
Xenon tetrafluoride is a silicone rubber decomposition agent, used for studying trace metal impurities. It reacts with the silicone matrix to form simple gaseous products, leaving behind a residue containing the metal impurities.[12]
References
- ^ a b Arnold F. Holleman; Egon Wiberg (2001). Nils Wiberg (ed.). Inorganic chemistry. translated by Mary Eagleson, William Brewer. Academic Press. p. 394. ISBN 0123526515.
- ^ a b Zumdahl (2007). Chemistry. Boston: Houghton Mifflin. p. 243. ISBN 0-618-52844-X.
- ^ Claassen, H. H.; Selig, H.; Malm, J. G. (1962). "Xenon Tetrafluoride". J. Am. Chem. Soc. 84 (18): 3593. doi:10.1021/ja00877a042.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ C. L. Chernick, H. H. Claassen, P. R. Fields 1, H. H. Hyman, J. G. Malm, W. M. Manning, M. S. Matheson, L. A. Quarterman, F. Schreiner, H. H. Selig, I. Sheft, S. Siegel, E. N. Sloth, L. Stein, M. H. Studier, J. L. Weeks, and M. H. Zirin (1962). "Fluorine Compounds of Xenon and Radon". Science. 138 (3537): 136–138. doi:10.1126/science.138.3537.136. PMID 17818399.
{{cite journal}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link) - ^ Thomas H. Brown, E. B. Whipple, and Peter H. Verdier (1963). "Xenon Tetrafluoride: Fluorine-19 High-Resolution Magnetic Resonance Spectrum". Science. 140 (3563): 178. doi:10.1126/science.140.3563.178. PMID 17819836.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ James A. Ibers and Walter C. Hamilton (1963). "Xenon Tetrafluoride: Crystal Structure". Science. 139 (3550): 106–107. doi:10.1126/science.139.3550.106. PMID 17798707.
- ^ Burns, John H.; Agron, P. A.; Levy, Henri A. "Xenon Tetrafluoride Molecule and Its Thermal Motion: A Neutron Diffraction Study". Science. 139 (3560): 1208–1209.
- ^ a b c Allen J. Bard; Roger Parsons; Joseph Jordan; International Union of Pure and Applied Chemistry (1985). Standard Potentials in Aqueous Solution. CRC Press. pp. 767–768. ISBN 0824772911.
- ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1126/science.139.3559.1046, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1126/science.139.3559.1046instead. - ^ Hitomi Suzuki; Yoshihiro Matano (2001). Organobismuth chemistry. Elsevier. p. 8. ISBN 0444205284.
- ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1039/C29710001543, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1039/C29710001543instead. - ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/S0003-2670(96)00563-6, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1016/S0003-2670(96)00563-6instead.