Thorium (Th)
Thorium
Thorium (Th) is an actinide in period 7. Its relative atomic mass is 232.04 and the molar mass of the atom is 232.04 g/mol.
Atomic number 90
Atomic mass 232.04
Molar mass 232.04 g/mol
Category Actinide Solid
Properties of thorium
| Atomic number | 90 |
|---|---|
| Symbol | Th |
| Latin name | Thorium |
| Relative atomic mass | 232.04 |
| Molar mass | 232.04 g/mol |
| Group, period, block | —, 7, f |
| Category | Actinide |
| State at 20 °C | Solid |
| Electron configuration | [Rn] 6d² 7s² |
| Electronegativity (Pauling) | 1.3 |
| Atomic radius | 180 pm |
Electron configuration of thorium
Electrons per shell
K2L8M18N32O18P10Q2
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁶ 6d² 7s²
Noble-gas notation
90 protons · 90 electrons[Rn] 6d² 7s²
Formula and compounds of thorium
Simple substanceThthoriumMolar mass of Th: 232.04 g/mol
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Frequently asked questions
The relative atomic mass of thorium is 232.04, so the molar mass of the atom is 232.04 g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁶ 6d² 7s². Noble-gas notation: [Rn] 6d² 7s².