Xenon trioxide difluoride

Xenon Trioxide Difluoride and Xenon Dioxide Tetrafluoride... 

In the preparation of xenon difluoride dioxide from caesium nitrate and xenon tetrafluoride oxide, the latter must always be used in excess to prevent formation of explosive xenon trioxide. 

Although uncontrolled reaction of xenon hexafluoride and moisture produces explosive xenon trioxide, controlled action by progressive addition of limited amounts of water vapour with agitation to a frozen solution of the hexafluoride in anhydrous hydrogen fluoride at —196° C to give xenon oxide tetrafluoride or xenon dioxide difluoride is safe [1], Controlled hydrolysis in solution in hydrogen fluoride is, however, described as hazardous [2],... 

In the reaction of the pentaoxide with xenon tetrafluoride oxide to give xenon difluoride dioxide and nitryl fluoride, the xenon tetrafluoride oxide must be used in excess to avoid formation of xenon trioxide, which forms a sensitive explosive mixture with xenon difluoride dioxide. 

Tetrafluoroammonium hexafluoromanganate, 4384 Tetrafluoroammonium hexafluoronickelate, 4385 Tetrafluoroammonium hexafluoroxenate Tetranitromethane, 0546 Titanium tetraperchlorate, 4170 1,1,1 -Triacetoxy-1,2-benziodoxol-3-one, 3610 Trifluoromethyl hypofluorite, 0353 Trimethylsilyl chlorochromate, 1301 Trioxygen difluoride , 4323 Uranium hexafluoride, 4375 Vanadium(V) oxide, 4866 Vanadium trinitrate oxide, 4763 Vanadyl perchlorate, 4152 Xenon hexafluoride, 4377 Xenon(II) pentafluoroorthoselenate, 4382 Xenon(II) pentafluoroorthotellurate, 4383 Xenon tetrafluoride, 4353 Xenon tetrafluoride oxide, 4346 Xenon tetraoxide, 4863 Xenon trioxide, 4857 Zinc permanganate, 4710... 

Xenon Dioxide Difluoride. Xe02F2 mw 201.30 colorl solid, liq vap mp 30.80°.Prepn is by distilling Xe oxytetrafluoride into Xe trioxide at dry ice temp, and then fractionally distilling off the unreacted Xe oxytetrafluoride along with the by-product Xe difluoride, leaving the product. According to Holloway, samples of Xe dioxide-difluoride have expld Refs 1) J.H. Holloway, Noble Gas Chemistry , Methuen, London (1968), 132-34 2) J.C. 

Xenon difluoride dioxide, 4316 Xenon difluoride oxide, 4313 Xenon difluoride, 4326 Xenon hexafluoride, 4371 Xenon(II) fluoride methanesulfonate, 0442 Xenon(II) fluoride perchlorate, 3971 Xenon(II) fluoride trifluoroacetate, 0630 Xenon(II) fluoride trifluoromethanesulfonate, 0355 Xenon(II) pentafluoroorthoselenate, 4376 Xenon(II) pentafluoroorthotellurate, 4377 Xenon(IV) hydroxide, 4528 Xenon tetrafluoride oxide, 4340 Xenon tetrafluoride, 4347 Xenon tetraoxide, 4857 Xenon trioxide, 4851 Xenon, 4920 t mixo-Xylene, 2964 t m-Xylene, 2966 t o-Xylene, 2965 t p-Xylene, 2967... 

In view of the instability of the trioxide it is interesting to speculate on the stability of the oxyfluorides. Xenon oxide tetrafluoride should be an exothermic compound since the atomic heat of formation using average bond energies of 32 kcal. and 17 kcal. respectively for Xe-F and Xe-O is —160 kcal. mole-. The combined heat of atomization of four fluorine atoms (4 x 18.3 kcal.) and one oxygen atom (59.2 kcals.), 132.4 kcal., is less than this. Xenon dioxide difluoride, by such considerations, should be endothermic. It is of interest that xenon oxide tetrafluoride is easily made by controlled hydrolysis of xenon hexafluoride and is a thermally stable entity (m.p. —28) whereas xenon dioxide difluoride has been observed only mass spectrometrically < >. 

Shortly after publication of the observations on the synthesis of xenon tetrafluoride, research was initiated with the noble gases in a number of laboratories. Xenon difluoride, xenon hexafluoride, xenon oxide tetrafluoride, and xenon trioxide were synthesized and reasonably well characterized within a rather short time. A number of other compounds have since been isolated, including xenon tetraoxide, a family of perxenates, and a variety of complex fluorides such as XeF2-2SbF5, XeFe BFs, and CsjXeFs. 

Xenon difluoride dissolves in water, yielding a solution which contains undissociated XeFa molecules which have a half-life of about 7 hours at 0°. It eventually hydrolyzes to yield the expected products, xenon, hydrogen fluoride, and oxygen. The hydrolysis reactions of the tetrafluoride and hexafluoride are somewhat more complicated. The addition of the stoichiometric amount of water to the hexafluoride results in the formation of xenon oxide tetrafluoride. Hydrolysis of either fluoride with an excess of water or acid yields in solution a stable xenon(VI) species, which has been shown to be hydrated xenon trioxide. Removal of the excess water leaves xenon trioxide as a solid residue. Inasmuch as this solid is an extremely sensitive explosive, such solutions must be handled with care. 

An initial 1 1 F Xe mixture will leave some imreacted xenon because of loss of fluorine to the glass, but pure XeF is produced in this way. F2.-Xe ratios greater than 1 or additional increments of fluorine to the. xenon difluoride produce xenon tetrafluoride. (Care must be taken in handling xenon tetrafluoride because xenon trioxide can be produced from it. )... 

Potassium hexaoxoxenonate-xenon trioxide, 4674 Tetrafluoroammouium hexalluoroxenate, 4386 Xenon difluoride dioxide, 4322... 

Xenon hexafluoride is a better fluorinating agent than the xenon difluoride described in the previous problem, but it must be carefully isolated from any moisture. This is because xenon hexafluoride reacts with water to form hydrogen fluoride (hydrogen monofluoride) and the dangerously explosive xenon trioxide. 

The xenon fluorides were synthesized by the direct reaction of the element shortly after Bartlett s announcement. The tetrafluoride is the stablest and best characterized, although its hydrolysis yields the dangerously explosive xenon trioxide. Xenon difluoride is an excellent oxidizing agent and fluoride ion donor. Xenon hexafluoride is both a fluoride donor and acceptor. 

Other xenon halides include the dichloride, the tetrachloride, and the dibromide, but these are not particularly stable. Solutions of xenon trioxide, called xenic acid, are excellent oxidizing agents, as is the octahedral perxenate anion, XeOg. Krypton difluoride, a few nitrogen compounds of both xenon and krypton, and radon difluoride have also been prepared but are not well-characterized. 

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