Xenon is a member of Group VIIIA (Group 18), the so-called rare gases. It is in the 5th period. Other members of the group are helium (He), neon (Ne), argon (Ar), krypton (Kr), and radon (Rn).
The elemental gas was discovered in 1898 by Ramsay and Travers in the residue left after fractionation of kryton.
The name is derived from the Greek word, xenon, meaning the stranger. The symbol Xe is an abbreviation of the name.
Xenon, a colorless gas, is present in the atmosphere in extremely minute quantities (about 1 part in 20 million; much less than Kr) and is produced commercially as a byproduct in the preparation of liquid air. One of the rare gases, it is characterized by its beautiful blue glow when excited in a discharge tube. In the solid state, the element has a face-centered cubic structure.
The gas is used in electron tubes, stroboscopic lamps, bactericidal lamps, and projection lamps. Xenon is also readily soluble in blood and acts as an inhalation anesthetic in much the same way as N2O, "laughing gas".
Although often called the "inert gases", at least Xe of the elements in Group VIIIA is not chemically inert. The discovery of the first rare gas compound in 1962 provides us with a lesson that the most interesting discoveries are often the result of lucky accidents and of being prepared to interpret an observation in a new way. While studying the chemistry of PtF6, Neil Bartlett noticed, quite by accident, that exposing it to air led to a compound that he showed to be [O2][PtF6]. Just as important, Bartlett realized that the ionization energy of O2 (to give O2 with a single positive charge) was about the same as that of Xe. Thus, he quickly treated PtF6 with Xe and discovered XePtF6, the first true compound of a rare gas. Soon after this, he and others found a large number of compounds of xenon, among them XeF2, XeF4, XeF6, and XeO3.