Atomic number 54
Xenon
Noble gas
In the real world
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 dangerous is it?
1/5 · Low risk
A non-toxic, unreactive gas. It is heavy and, like other inert gases, can quietly crowd out the air you need to breathe in a sealed space.
- AsphyxiantImmediate
It is not poisonous; it is a concern only because it can push oxygen out of a closed space, and being heavy it can pool low. (the danger is the room, not the gas itself)
Used with good ventilation; sealed rooms are checked with an oxygen monitor.
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.
