Xenon hexafluoride

Structural formula
General
Surname	Xenon hexafluoride
other names	Xenon (VI) fluoride
Molecular formula	XeF 6
Brief description	colorless solid
External identifiers / databases
CAS number 13693-09-9 PubChem 139546 ChemSpider 123066 Wikidata Q411142
properties
Molar mass	245.28 g mol −1
Physical state	firmly
density	3.56 g cm −3
Melting point	49.5 ° C
boiling point	75.6 ° C
Vapor pressure	40 hPa (25 ° C)
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Xenon hexafluoride is a chemical compound from the group of noble gas compounds . It is a colorless solid.

Manufacturing

All xenon fluorides are produced by thermal or photochemical activation of xenon / fluorine mixtures. Which product is formed depends on the molar ratio and the reaction conditions (pressure, temperature). Xenon hexafluoride can be obtained by long-term heating of xenon with a strong fluorine excess (1:20) at 300 ° C and a pressure of 200-300 bar.

${\displaystyle {\ce {Xe + 3F2 -> XeF6}}}$

The purification can be done by decomposing disodium fluoroxenate (VI) at 120 ° C.

${\displaystyle {\ce {Na2XeF8 <=> XeF6 + 2 NaF}}}$

properties

Physical Properties

The molecule has a distorted octahedral structure in the gas phase , the xenon-fluorine distance in the gaseous state being 189 pm. In the solid state, xenon (VI) fluoride consists of and ions, which bridge to tetrameric or hexameric rings. At low temperatures, the compound also forms tetramers when dissolved in non-ionizing media. In addition to the tetramers, the yellow-green melt of the compound is also composed of monomers and has a low intrinsic conductivity. The yellow color that occurs during heating is reversible, so that the solid is colorless again after the melt has cooled. ${\displaystyle {\ce {[XeF5]+}}}$ ${\displaystyle {\ce {F-}}}$

Chemical properties

Of all the xenon fluorides, xenon hexafluoride is the most strongly oxidizing compound and so far could not be further oxidized. It reacts as both a fluoride acceptor and a donor. In general, the compound reacts with metal fluorides of the type such as antimony pentafluoride as a donor. ${\displaystyle {\ce {MF_{J}}}}$

${\displaystyle {\ce {XeF6 + MF_{J}-> [XeF5][MF_{J + 1}]}}}$

On the other hand, xenon (VI) fluoride reacts with alkali metal fluorides as an acceptor to form hexavalent fluoroxenates , of which the salts of the higher homologues with the doubly negative anion have the highest stability.

${\displaystyle {\ce {XeF6 + MF -> M[XeF7]}}}$

${\displaystyle {\ce {XeF6 + 2MF -> M2[XeF8]}}}$

Xenon hexafluoride hydrolyzes gradually to form xenon trioxide .

${\displaystyle {\ce {XeF6 + H2O -> XeOF4 + 2HF}}}$

${\displaystyle {\ce {XeOF4 + H2O -> XeO2F2 + 2HF}}}$

${\displaystyle {\ce {XeO2F2 + H2O -> XeO3 + 2HF}}}$

use

By hydrolysis can Xenonoxytetrafluorid be established.

${\displaystyle {\ce {XeF6 + H2O -> XeOF4 + 2 HF}}}$

See also

• Xenon difluoride XeF ₂
• Xenon tetrafluoride XeF ₄

Individual evidence

1. ↑ ^{a b c d} C. L. Chernick and JG Malm: Xenon hexafluoride . In: Henry F. Holtzclaw, Jr. (Ed.): Inorganic Syntheses . tape 8 . McGraw-Hill Book Company, Inc., 1966, pp. 258-260 (English).
2. ↑ data sheet at Webelements .
3. ↑ ^{a b c} Entry on Xenon connections. In: Römpp Online . Georg Thieme Verlag, accessed on January 3, 2018.
4. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
5. ^ ^{A b} Arnold F. Hollemann, Nils E. Wiberg: Inorganic Chemistry . tape 1 . de Gruyter, Berlin 2017, ISBN 978-3-11-026932-1 , p. 467-468 .
6. ^ SK Jain, Shailesh K. Jain: Conceptual Chemistry Volume-I For Class XII . S. Chand Publishing, ISBN 81-219-1623-2 , pp. 7-127 .