54
Xe
Xenon
131.293
Xenon (Xe)
Noble GasGroup 18Period 5p-block-block
Xenon is a chemical element with symbol Xe and atomic number 54. It is a colorless, dense, odorless noble gas, that occurs in the Earth's atmosphere in trace amounts. 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.
Latin name: Xenon
Atomic Number
54
Atomic Mass
131.293 g/mol
Phase (STP)
Gas
Electron Config.
[Kr] 4d¹⁰ 5s² 5p⁶
General
SymbolXe
Atomic Number54
Atomic Mass131.293 g/mol
CategoryNoble Gas
Group18
Period5
Blockp-block
Electron Configuration[Kr] 4d¹⁰ 5s² 5p⁶
Valence Electrons8
Colourcolorless
Appearancecolorless gas, exhibiting a blue glow when placed in a high voltage electric field
CAS NumberCAS7440-63-3
Physical Properties
Phase (STP)Gas
Density0.005887 g/cm³
Melting Point-111.79°C · -169.22°F · 161.36 K
Boiling Point-108.12°C · -162.62°F · 165.03 K
Atomic Properties
Atomic Radius108 pm
Electronegativity2.6 Pauling
Ionization Energy1170 kJ/mol
Oxidation States+8, +6, +4, +2, 0
Ion ChargeXe2+/Xe6+
Crystal Structure
Crystal Structureface-centered cubic (solid)
Nuclear & Hazards
Half-lifestable
Abundance
In Universe0.000009%
In Sun0.000008%
In Earth's Crust0.0000000001%
In Oceans0.0000003%
Discovery & History
Discovery Year1898
Discovered ByWilliam Ramsay, Morris Travers
Country of DiscoveryEngland
Isotopes of Xenon
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| Xe-124 | 0.095% | Stable | — |
| Xe-126 | 0.089% | Stable | — |
| Xe-128 | 1.91% | Stable | — |
| Xe-129 | 26.401% | Stable | — |
| Xe-130 | 4.071% | Stable | — |
| Xe-131 | 21.232% | Stable | — |
| Xe-132 | 26.909% | Stable | — |
| Xe-134 | 10.436% | Stable | — |
| Xe-136 | 8.857% | 2.165 × 10²¹ years | β⁻β⁻ |