Radon (Rn)

Colorless gas

Radon is a radioactive noble gas that seeps from the ground and is the leading cause of lung cancer after smoking, and with a filled 6p⁶ shell, radon-222 (half-life 3.8 days) is a dense gas (9.73 kg/m³) that accumulates in basements and mines. It decays through a chain of short-lived daughters that lodge in lung tissue.

Key metrics

Density0.00973g/cm³

Melting point202K

Boiling point211K

Electronegativity2.2Pauling

Discovery

1900discovered

Discovered by: Friedrich Ernst Dorn
Reactivity profile: Radioactive noble gas
Reactivity: Low
Bonding: Covalent

Electron configuration

\textcolor{#6b7280}{[Xe]}\; \textcolor{#a855f7}{4_{f}^{14}}\; \textcolor{#22c55e}{5_{d}^{10}}\; \textcolor{#ef4444}{6_{s}^{2}}\; \textcolor{#3b82f6}{6_{p}^{6}}

[Xe] 4f14 5d10 6s2 6p6

Wave function

\Psi_{\text{Rn}} \approx \frac{1}{\sqrt{86!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{86}(\mathbf{r}_{86}) \right|

Probability density $|\Psi|^2$ across the Rn valence shell.

Crystal structure

Face-Centered Cubic

Lattice constantsa = 1.00

Cell anglesα = β = γ = 90°

Coordination number12

Atoms per cell4

Atomic packing factor0.74

Physical properties

Atomic radius: 120 pm
Ionization energy: 1037 kJ/mol
Electron affinity: 0 kJ/mol
Crystal structure: Face-centered cubic

Oxidation states

0+2

Acid/base

Neutral

Strongly acidicStrongly basic

State at 25 °CGas

202 K211 K298 K

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

584.2nmRn I (yellow)Yellow50%

654.7nmRn I (red)Red70%

692.5nmRn I (red)Red100%

Dominant line 692.5 nmRange 584–693 nmTransitions 3