Periodic TableRadon (Rn)
Radon is a noble gas with atomic number 86, in period 6 and group 18 of the periodic table. Its atomic mass is 222 u and its electron configuration is [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁶. Gas at 25 °C.
Key facts
| Atomic number | 86 |
|---|---|
| Atomic mass | 222 u |
| Category | Noble Gas |
| Period | 6 |
| Group | 18 |
| Block | p |
| Electron configuration | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁶ |
| Electrons per shell | 2, 8, 18, 32, 18, 8 |
| Electronegativity (Pauling) | --- |
| Oxidation states | +2, +6common in bold |
| State at 25 °C | Gas |
| Melting point | 202 K−71.15 °C |
| Boiling point | 211.3 K−61.85 °C |
| Density | 9.73 g/L |
Atomic properties
| First ionization energy | 10.749 eV |
|---|---|
| Electron affinity | 0 kJ/mol |
| Atomic radius | 214 pm |
| Covalent radius | 150 pm |
| Van der Waals radius | 220 pm |
| Common ions | --- |
| Protons, neutrons, electrons | 86, 136, 86 |
Physical and thermal properties
| Molar volume | 50.5 cm³/mol |
|---|---|
| Heat of fusion | 3 kJ/mol |
| Heat of vaporization | 17 kJ/mol |
| Specific heat | 93.65 J/(kg·K) |
| Thermal conductivity | 0.00361 W/(m·K) |
| Thermal expansion | --- |
| Mohs hardness | --- |
| Young’s modulus | --- |
| Crystal structure | --- |
| Magnetic type | Diamagnetic |
Identification and history
| CAS number | 10043-92-2 |
|---|---|
| Latin name | Radon |
| Discovered by | E. Rutherford, R. Owens · 1899 |
| Named by | --- |
Natural isotopes
Radon has no stable isotopes: every isotope is radioactive.
Data checked against PubChem (NIH), IUPAC, the NIST Atomic Spectra Database and the IAEA (NUBASE and AME), the same data you see in the app.
A dash (---) means there is no reliable published measurement. The app never makes one up.
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