Symbol: Xe
Atomic number: 54
Category: noble gases
Group: 18
Period: 5
Block: p
Atomic weight: 131.293 g/mol
Electrons per shell: 2, 8, 18, 18, 8
CAS number: 7440-63-3
Phase: gas
Density: 5.894 g/l (0C, 101.325 kPa)
Melting point: (101.325 kPa) 161.4 K (-111.7 C,
Boiling point: (101.325 kPa) 165.03 K (-108.12 C,
Crystal structure: cubic face centered
Oxidation states: 0, 1, 2, 4, 6, 8
Electronegativity: 2.6 (Pauling scale)
Name's origin: xenos
Name's meaning: a Greek word which means 'stranger' because it's found so little in the Earth's atmosphere
- occurs in the Earth's atmosphere in trace amounts (0.087 ppm)
- although generally unreactive, xenon can undergo a few chemical reactions such as the formation of xenon hexafluoroplatinate, the first noble gas compound to be synthesized
- is used in flash lamps and arc lamps, and as a general anesthetic
- is also being used to search for hypothetical weakly interacting massive particles and as the propellant for ion thrusters in spacecraft
- can be safely kept in normal sealed glass or metal containers at standard temperature and pressure, although it readily dissolves in most plastics and rubber, and will gradually escape from a container sealed with such material
- naturally occurring xenon consists of nine stable isotopes, and there are also over 40 unstable isotopes that undergo radioactive decay