Xenon difluoride
Xenon (II ) fluoride
Colorless crystals
Fixed
4.32 g · cm -3
114.35 ° C
5.2 hPa ( 25 ° C)
Hydrolysis in water
Risk
Fluoride 2.5 mg · m-3 respirable dust fraction (calculated as the fluorides)
Template: Infobox chemical / molecular formula search available
Xenon ( di ) fluoride ( XeF 2 ) is a colorless, crystalline noble gas compound. It was first synthesized in 1962 as a third compound of a noble gas by Xenonhexafluoroplatinat ( XePtF6 ) and xenon tetrafluoride by Rudolf Hoppe. Under special conditions, Xenon reacts with fluorine to this substance.
Representation
Direct Synthesis of xenon, and fluorine in the gas phase, with the aid of catalysts such as hydrogen fluoride or nickel (II ) fluoride, as well as irradiation with UV light.
Properties
Physical Properties
At normal pressure and a temperature of 114.35 ° C, it goes through sublimation directly from solid to gaseous state. The triple point where the three phases, liquid and gas are determined in equilibrium, is at a temperature of 129.03 ° C.
Chemical Properties
The rapid heating of the air is divided to xenon difluoride and fluorine. Despite the negative enthalpy of formation () This reaction proceeds explosively, as a large increase in volume takes place. Xenon difluoride crystals have tetragonal symmetry. The crystal lattice contains isolated XeF 2 molecules; Xenon fluorine distance is 198 pm.
Use
Xenon (II ) fluoride is used as a strong oxidation and fluorinating agent in organic synthesis, for example, of the aromatic fluorination. A mixture of magnesium and xenon (II ) fluoride burns with a 2575 K hot flame.
Other noble gas compounds
Sometimes could further xenon compounds (especially chlorides, oxides ), but also the crypto connection Kryptondifluorid ( KrF2 ) are produced. In addition, it is thought that there must be parallel to xenon, radon, various oxides and halides. Most noble gas compounds are compared to xenon difluoride much less stable and often highly explosive. The reactivity of the noble gases will probably increase with increasing atomic weight so that Radondifluorid theoretically this should still be slightly more stable than XeF2.