Xenon

Element 54 · Noble gas

Specimen

Atomic number: 54
Atomic mass: 131.29
State at room temperature: Gas
Melting point: -111.8 °C
Boiling point: -108.1 °C
Density: 0.005887 g/cm³
Discovered: 1898

Physical data from PubChem.¹

Can I eat it?

In food and water: Not needed, little harm known. Xenon is a gas with no known function in the body. The RSC says xenon itself is not toxic. Its compounds are highly toxic because they are strong oxidizers. ²

The atom

Shell	Electrons
1 (K)	2
2 (L)	8
3 (M)	18
4 (N)	18
5 (O) outermost	8
Total	54

Configuration [Kr] 4d¹⁰ 5s² 5p⁶

4d ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓ ↑ ↓

5s ↑ ↓

5p ↑ ↓ ↑ ↓ ↑ ↓

A shell diagram: each ring is an electron shell and each dot is one electron. The nucleus holds 54 protons. The outermost shell is shown in red. Electrons do not travel on rings: they fill orbitals, regions where an electron is likely to be found. The boxes are those orbitals for the electrons outside the Kr core, with one arrow per electron.

Related elements

Sources

1

National Center for Biotechnology Information (PubChem), 2026. Periodic Table of Elements .

Atomic mass, electron configuration, melting and boiling points, density and discovery year for all 118 elements.
2
Royal Society of Chemistry, 2026. Xenon - Element information, properties and uses .
- Xenon has no known biological role. It is not itself toxic, but its compounds are highly toxic because they are strong oxidising agents.

Specimen

Can I eat it?

The atom

Related elements

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Sources