Xenon tetrafluoride
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Names | |||
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IUPAC name Xenon tetrafluoride | |||
Identifiers | |||
3D model (JSmol) | |||
ChemSpider | |||
ECHA InfoCard | 100.033.858 | ||
PubChem CID | |||
UNII | |||
CompTox Dashboard (EPA) | |||
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Properties | |||
XeF 4 | |||
Molar mass | 207.2836 g mol−1 | ||
Appearance | White solid | ||
Density | 4.040 g cm−3, solid | ||
Melting point | 117 °C (243 °F; 390 K) sublimes[1] | ||
Reacts | |||
Structure | |||
D4h | |||
square planar | |||
0 D | |||
Thermochemistry | |||
Std molar entropy (S⦵298) | 146 J·mol−1·K−1[2] | ||
Std enthalpy of formation (ΔfH⦵298) | −251 kJ·mol−1[2] | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Xenon tetrafluoride is a chemical compound with chemical formula XeF
4. It was the first discovered binary compound of a noble gas.[3] It is produced by the chemical reaction of xenon with fluorine:[4][5]
- Xe + 2 F
2 → XeF
4
This reaction is exothermic, releasing an energy of 251 kJ/mol.[3]
Xenon tetrafluoride is a colorless crystalline solid that sublimes at 117 °C. Its structure was determined by both NMR spectroscopy and X-ray crystallography in 1963.[6][7] The structure is square planar, as has been confirmed by neutron diffraction studies.[8] According to VSEPR theory, in addition to four fluoride ligands, the xenon center has two lone pairs of electrons. These lone pairs are mutually trans.
Synthesis
[edit]Xenon tetrafluoride is produced by heating a mixture of xenon and fluorine in a 1:5 molar ratio in a nickel container to 400 °C. Some xenon difluoride (XeF
2) and xenon hexafluoride (XeF
6) is also produced, where increased temperature or decreased fluorine concentration in the input mixture favors XeF
2 production, and decreased temperature or increased fluorine concentration favors XeF
6.[9][10] The nickel is not a catalyst for this reaction; nickel containers are used because they react with fluorine to form a protective, non-peeling passivation layer of nickel(II) fluoride NiF
2 on their interior surfaces. The low volatility of XeF
4 compared to XeF
2 and XeF
6 allows it to be purified by fractional sublimation.[9]
Reactions
[edit]Xenon tetrafluoride hydrolyzes at low temperatures to form elemental xenon, oxygen, hydrofluoric acid, and aqueous xenon trioxide:[11]
It is used as a precursor for synthesis of all tetravalent Xe compounds.[9] Reaction with tetramethylammonium fluoride gives tetramethylammonium pentafluoroxenate, which contains the pentagonal XeF−
5 anion. The XeF−
5 anion is also formed by reaction with cesium fluoride:[12]
- CsF + XeF
4 → CsXeF
5
Reaction with bismuth pentafluoride (BiF
5) forms the XeF+
3 cation:[13]
- BiF
5 + XeF
4 → XeF3BiF6
The XeF+
3 cation in the salt XeF3Sb2F11 has been characterized by NMR spectroscopy.[14]
At 400 °C, XeF
4 reacts with xenon to form XeF
2:[10]
- XeF4 + Xe → 2 XeF2
The reaction of xenon tetrafluoride with platinum yields platinum tetrafluoride and xenon:[10]
- XeF4 + Pt → PtF4 + Xe
Applications
[edit]Xenon tetrafluoride has few applications. It has been shown to degrade silicone rubber for analyzing trace metal impurities in the rubber. XeF
4 reacts with the silicone to form simple gaseous products, leaving a residue of metal impurities.[15]
References
[edit]- ^ Holleman, Arnold F.; Wiberg, Egon (2001). Wiberg, Nils (ed.). Inorganic Chemistry. Translated by Eagleson, Mary; Brewer, William. Academic Press. p. 394. ISBN 0-12-352651-5.
- ^ a b Zumdahl, Steven S. (2009). Chemical Principles (6th ed.). Houghton Mifflin Company. p. A23. ISBN 978-0-618-94690-7.
- ^ a b Zumdahl (2007). Chemistry. Boston: Houghton Mifflin. p. 243. ISBN 978-0-618-52844-8.
- ^ Claassen, H. H.; Selig, H.; Malm, J. G. (1962). "Xenon Tetrafluoride". J. Am. Chem. Soc. 84 (18): 3593. doi:10.1021/ja00877a042.
- ^ Chernick, C. L.; Claassen, H. H.; Fields, P. R.; Hyman, H. H.; Malm, J. G.; Manning, W. M.; Matheson, M. S.; Quarterman, L. A.; Schreiner, F.; Selig, H. H.; Sheft, I.; Siegel, S.; Sloth, E. N.; Stein, L.; Studier, M. H.; Weeks, J. L.; Zirin, M. H. (1962). "Fluorine Compounds of Xenon and Radon". Science. 138 (3537): 136–138. Bibcode:1962Sci...138..136C. doi:10.1126/science.138.3537.136. PMID 17818399. S2CID 10330125.
- ^ Brown, Thomas H.; Whipple, E. B.; Verdier, Peter H. (1963). "Xenon Tetrafluoride: Fluorine-19 High-Resolution Magnetic Resonance Spectrum". Science. 140 (3563): 178. Bibcode:1963Sci...140..178B. doi:10.1126/science.140.3563.178. PMID 17819836. S2CID 35981023.
- ^ Ibers, James A.; Hamilton, Walter C. (1963). "Xenon Tetrafluoride: Crystal Structure". Science. 139 (3550): 106–107. Bibcode:1963Sci...139..106I. doi:10.1126/science.139.3550.106. PMID 17798707. S2CID 42119788.
- ^ Burns, John H.; Agron, P. A.; Levy, Henri A (1963). "Xenon Tetrafluoride Molecule and Its Thermal Motion: A Neutron Diffraction Study". Science. 139 (3560): 1208–1209. Bibcode:1963Sci...139.1208B. doi:10.1126/science.139.3560.1208. PMID 17757912. S2CID 35858682.
- ^ a b c Haner, Jamie; Schrobilgen, Gary J. (2015). "The Chemistry of Xenon(IV)". Chem. Rev. 115 (2): 1255–1295. doi:10.1021/cr500427p. ISSN 0009-2665. PMID 25559700.
- ^ a b c Bard, Allen J.; Parsons, Roger; Jordan, Joseph; International Union of Pure and Applied Chemistry (1985). Standard Potentials in Aqueous Solution. CRC Press. pp. 767–768. ISBN 0-8247-7291-1.
- ^ Williamson; Koch, C. W. (Mar 1963). "Xenon Tetrafluoride: Reaction with Aqueous Solutions". Science. 139 (3559): 1046–1047. Bibcode:1963Sci...139.1046W. doi:10.1126/science.139.3559.1046. ISSN 0036-8075. PMID 17812981. S2CID 33320384.
- ^ Harding, Charlie; Johnson, David Arthur; Janes, Rob (2002). Elements of the p Block. Molecular World. Vol. 9. Royal Society of Chemistry. p. 93. ISBN 0-85404-690-9.
- ^ Suzuki, Hitomi; Matano, Yoshihiro (2001). Organobismuth chemistry. Elsevier. p. 8. ISBN 0-444-20528-4.
- ^ Gillespie, R. J.; Landa, B.; Schrobilgen, G. J. (1971). "Trifluoroxenon(IV) µ-fluoro-bispentafluoroantimonate(V): the XeF+
3 cation". Journal of the Chemical Society D: Chemical Communications (23): 1543–1544. doi:10.1039/C29710001543. - ^ Rigin, V.; Skvortsov, N. K.; Rigin, V. V. (March 1997). "Xenon tetrafluoride as a decomposition agent for silicone rubber for isolation and atomic emission spectrometric determination of trace metals". Analytica Chimica Acta. 340 (1–3): 1–3. Bibcode:1997AcAC..340....1R. doi:10.1016/S0003-2670(96)00563-6.