Xenon
A heavy noble gas used in lamps and ion thrusters.
Inside the Xenon atom
Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Xenon atom step by step.
Electron configuration
[Kr] 4d10 5s2 5p6
A neutral Xenon atom has 54 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.
Shell distribution
Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.
Physical & atomic properties
- State (room temp)
- Gas
- Melting point
- 161 K (-112 °C)
- Boiling point
- 165 K (-108 °C)
- Density
- 0.005887 g/cm³
- Electronegativity
- 2.6 Pauling
- Atomic radius
- 108 pm
- 1st ionization energy
- 1170 kJ/mol
- Category
- Noble gases
Discovery & naming
- Discovered
- 1898
- Discovered by
- William Ramsay and Morris Travers
- Origin of name
- Greek 'xenos', meaning stranger.
Notable uses
Bright lamps, anaesthesia, and spacecraft ion thrusters.
Where Xenon comes from
Several comparable sources
Both slow neutron capture in dying stars and rapid capture in explosive events contribute meaningfully.
Simplified origin map — many elements form through more than one astrophysical pathway.
Summary
- Atomic number
- 54
- Atomic mass
- 131.29
- Category
- Noble gases
- Group · Period
- 18 · 5
- Block
- p-block
- Shells
- 2 · 8 · 18 · 18 · 8