Radon (Rn) – element 86
Radon is a chemical element with the symbol Rn and atomic number 86. It is a noble gas in group 18 (noble gases), period 6 of the periodic table (p-block), and is a gas at room temperature.
Radon (Rn) has atomic number 86, atomic mass [222] and electron configuration [Xe] 4f14 5d10 6s2 6p6.
Radon facts
| Symbol | Rn |
|---|---|
| Atomic number | 86 |
| Atomic mass | [222] |
| Category | noble gas |
| Group | group 18 (noble gases) |
| Period | 6 |
| Block | p-block |
| Phase at 20 °C | Gas |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 |
| Noble-gas notation | [Xe] 4f14 5d10 6s2 6p6 |
| Electrons per shell | 2, 8, 18, 32, 18, 8 |
| Valence electrons | 8 |
Bohr model and shells
Radon has 86 electrons in 6 shells: 2, 8, 18, 32, 18, 8. Full configuration and noble-gas notation are in the table; work out any element or ion with the electron configuration calculator.
Physical and atomic properties
| Melting point | 202 K (-71.1 °C) |
|---|---|
| Boiling point | 211.5 K (-61.6 °C) |
| Density | 9.73 g/L |
| Electronegativity (Pauling) | 2.2 |
| Electron affinity | -68 kJ/mol |
| Ionization energies | 1037 kJ/mol (1st) |
| Discovered by | Friedrich Ernst Dorn |
Use the atomic mass in the molar mass calculator for any formula containing Rn.
Position in the periodic table
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Frequently asked questions
What is the atomic mass of radon?
The atomic mass of radon is [222] (mass number of its longest-lived isotope, since it has no stable isotope).
What is the electron configuration of radon?
Radon has 86 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶, or [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁶ in noble-gas notation. Electrons per shell: 2, 8, 18, 32, 18, 8.
How many valence electrons does radon have?
Radon has 8 valence electrons (group 18).
Is radon a metal?
No. Radon is a nonmetal (noble gas).
Where is radon on the periodic table?
Radon is in group 18 (noble gases), period 6, in the p-block.
Data: Periodic-Table-JSON (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.