Atomic number 54
Xenon
Noble gas
Quick facts
- Atomic mass
- 131.29
- Group
- 18
- Period
- 5
- State (STP)
- gas
- Electronegativity
- —
- Common ox. states
- 0, +2, +4, +6, +8
Properties
Electron configuration
[Kr] 4d¹⁰ 5s² 5p⁶
- Ionization energy
- 1170.4 kJ/mol
- Electron affinity
- -77.0 kJ/mol
- Melting point
- 161.40 K (-111.7 °C)
- Boiling point
- 165.05 K (-108.1 °C)
How it bonds
Xenon is the noble gas that broke the rule. In 1962 chemists made XeF₄, then XeF₂, XeF₆, XeO₃ — proving "noble" is not the same as "inert." Xenon's 5p electrons are far enough from the nucleus that very electronegative partners (F, O) can pry them off.