From the CRC handbook of Chemistry and Physics, CRC Press, Cleveland, 55th ed., 1974-75 "The Elements" by C.R. Hammond. page B-37
XENON (Gr. xenon, stranger), Xe; at. wt. 131.30; at. no. 54; m.p. -111.9 C; b.p. -107.1+/-3 C; density (gas) 5.887+/-0.009 g/l, sp. gr. (liquid) 3.52 (-109 C); valence usually 0. Discovered by Ramsay and Travers in 1898 in the residue left after evaporating liquid air components. Xenon is a member of the so-called noble or "inert" gases. It is present in the atmosphere to the extent of about one part in twenty million. The element is found in the gases evolved from certain mineral springs, and is commercially obtained by extraction form liquid air. Natural xenon is composed of nine stable isotopes. IN addition to these, twenty-two unstable nuclides and isomers have been characterized. Until recently, xenon has been considered inert and unable toform compounds with other elements. Those compounds that were occasionally reported in the literature were considered not to be true compounds. Evidence has been mounting in the past few years that xenon, as well as other members of the zero valence elements, do form compounds. Among the "compounds" of xenon now reported are xenon hydrate, sodium perxenate, xenon deuterate, difluoride, tetrafluoride, hexafluorride, and XePtF6 and XeRhF6. More recently, xenon trioxide, which is highly explosive, has been prepared. The structure of these substances is still open to question. Xenon in a vacuum tube produces a beautiful blue glow when excited by an electrical discharge. The gas is used in making electron tubes, stroboscopic lamps, bactericidal lamps, and lamps used to excite ruby lasers for generating coherent light. Xenon is used in the atomic energy field in bubble chanbers, probes, and other applications where its high molecuar weight is of value. It is also potentially useful as a gas for ion engines. The perxenates are used in analytical chemistry as oxidizing agents. Xe(133) and Xe(135) are produced by neutron irradiation in air-cooled nuclear reactors. Xe(133) has useful applications as a radioisotope. The element is avaialable in sealed glass containers for about $20/liter of gas at standard pressure. Xenon is not toxic, but its compounds are highly toxic because of their strong oxidizing characteristics.
