Naturally occurring xenon consists of nine stable isotopes. There are also over 40 unstable isotopes that undergo radioactive decay. The isotope ratios of xenon are an important tool for studying the early history of the Solar System. Xenon-135 is produced as a result of nuclear fission and acts as a neutron absorber in nuclear reactors.
Xenon is used in flash lamps and arc lamps, and as a general aesthetic. The first excimer laser design used a xenon dimer molecule (Xe2) as its lasing medium and the earliest laser designs used xenon flash lamps as pumps. Xenon is also being used to search for hypothetical weakly interacting massive particles and as the propellant for ion thrusters in spacecraft.
Xenon flashAn atom of xenon is defined as having a nucleus with 54 protons. At standard temperature and pressure, pure xenon gas has a density of 5.761 kg/m3. As a liquid, xenon has a density of up to 3.100 g/mL, with the density maximum occurring at the triple point. Under the same conditions, the density of solid xenon, 3.640 g/cm3, is larger than the average density of granite, 2.75 g/cm3. Using gigapascals of pressure, xenon has been forced into a metallic phase. Solid xenon changes from face-centered cubic (fcc) to hexagonal close packed (hcp) crystal phase under pressure and begins to turn metallic at about 140 GPa, with no noticeable volume change in the hcp phase. It is completely metallic at 155 GPa. When metalized, xenon looks sky blue because it absorbs red light and transmits other visible frequencies. Such behaviour is unusual for a metal and is explained by the relatively small widths of the electron bands in metallic xenon. Xenon is a member of the zero-valence elements that are called noble or inert gases. It is inert to most common chemical reactions (such as combustion, for example) because the outer valence shell contains eight electrons. This produces a stable, minimum energy configuration in which the outer electrons are tightly bound. However, xenon can be oxidized by powerful oxidizing agents, and many xenon compounds have been synthesized.
In a gas-filled tube, xenon emits a blue or lavenderish glow when the gas is excited by electrical discharge. Xenon emits a band of emission lines that span the visual spectrum, but the most intense lines occur in the region of blue light, which produces the coloration.
The base value of each unit of ranges between 5 and 25Ð per unit, with up to 3 units being found at any one time.
Presence on Mars: Very Rare
|Group 1 | Group 2 | Group 3 | Group 4 | Group 5 | Group 6|
|Group 3|||Antimony | Astatine | Barium | Bismuth | Cesium | Francium | Hafnium | Indium | Iodine | Iridium | Lanthanum | Lead | Mercury | |Osmium | Platinum | Polonium | Radium | Radon | Rhenium | Tantalum | Tellurium | Thallium | Tin | Tungsten | Xenon||