Radon chemistry

The chemistry of radon (II) was outlined by Stein in 1983 (14). Since then, evidence for radon in a higher oxidation state (RnF4 or RnF6) and a radon oxide (Rn03) has been claimed and disputed, and the ions, [HRn03]+, [HRnOJ-, and [RnOjFJ have been reported. 

This was further substantiated by reactions of radon with fluoroni-trogen salts and halogen-fluoride metal salts, and the development of a method of collecting radon from air using [02]+[SbF6] or [IF6]+[SbF6] (237). 

In Gmelins Handbuck der Anorganischen Chemie Busch-beck, K.-C., Lippert, W., and Slawisch, A., Eds. Erganzungswerk zur 8. Auflage Band 1, Edelgasverbindungen, Verlag Chemie, Weinheim, 1970. 

Bartlett, N. Sladky, F. O. In Comprehensive Inorganic Chemistry Trotman-Dickenson, A. F., Ed. Vol. 1, pp. 213-330. Pergamon Press, Oxford, 1973. 

(a) Hyman, H. H. (ed.) Noble Gas Compounds, University of Chicago Press, Chicago, 1963 (b) Moody, G. J. Thomas, J. D. R. Noble Gases and their Compounds, Pergamon Press, Oxford, 1964 (c) Claassen, H. H. The Noble Gases, D.C. Heath and Co., Boston, 1966. 

Claims by Russian workers that a higher fluoride of radon, RnF4 or RnFe, can be prepared in tracer experiments by heating radon, xenon, fluorine, bromine pentafluoride, and either sodium fluoride or nickel fluoride, and converted to RnOa by hydrolysis 240) appeared to others (235) to be due to the precipitation of radon as a solid complex, which is probably [RnFJJlNiFe]. However, the precipitation of CsXeOsF from aqueous solutions results in the coprecipitation of radon, and this has been taken by the Russian group as confirmation that RnOs is the product of hydrolysis of the fluoride formed 241). Furthermore, 

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The physico-chemical properties of radon and its decay products are presented in a series of reports primarily focusing on the decay products. However, Stein (1987) presents a review of his pioneering studies of radon chemistry and the reactions of radon with strong oxidizing agents. Although radon is not chemically active in indoor air, it is interesting to note that radon is not an "inert gas. 

There are no stable isotopes of radon and the longest lived natnral isotope, Rn, has a half-life of only 3.83 days. Experimental difficulties arise not only from the radiation hazard, but also from the decomposition caused by the radiation. The most detailed review of radon chemistry, to early 1981, was written by Stein. 

Radon chemistry is difficult to study because all of its isotopes are radioactive. 

Chemically, radon is a noble gas. As such, it is colorless, odorless, and almost chemically inert. Although radon is not chemically active, it is interesting to note that radon is not a totally inert gas either. Studies on radon chemistry have been reported in which compounds such as clathrates and complex fluorides have been formed. Compared with the other noble gases, radon is the heaviest and has the highest melting point, boiling point, critical temperature, and critical pressure. 

All radon chemistry, of necessity, has been done at the radiotracer level, precluding the possibility of obtaining detailed stmctural support for the species that are proposed. 

Note that the reaction products with entries in Table 19.1 are much abbreviated compared with the analogous tables of earlier groups. Only xenon and krypton react with fluorine to produce fluorides. Therefore, instead of following the usual format of describing the hydrides, oxides, hydroxides, and halides of these elements (most of which do not exist), we adopt a historical description of the synthesis of xenon compounds and then briefly expand the discussion to include the small number of examples drawn from krypton and radon chemistry. 

Radon chemistry is difficult to study because all of its isotopes are radioactive. The longest-lived isotope, radon-222,has a half-life of only 3.82 d (d = day). 

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