Astatine (At)
Astatine
Astatine (At) is a halogen in period 6, group 17. Its relative atomic mass is [210] and the molar mass of the atom is [210] g/mol.
Atomic number 85
Atomic mass [210] predicted
Molar mass [210] g/mol
Category Halogen Solid
Properties of astatine
| Atomic number | 85 |
|---|---|
| Symbol | At |
| Latin name | Astatine |
| Relative atomic mass | [210] |
| Molar mass | [210] g/mol |
| Group, period, block | 17, 6, p |
| Category | Halogen |
| State at 20 °C | Solid |
| Electron configuration | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵ |
| Electronegativity (Pauling) | 2.2 |
Electron configuration of astatine
Electrons per shell
K2L8M18N32O18P7
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁵
Noble-gas notation
85 protons · 85 electrons[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵
Formula and compounds of astatine
Simple substanceAtastatineMolar mass of At: [210] g/mol
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Frequently asked questions
The relative atomic mass of astatine is [210], so the molar mass of the atom is [210] g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁵. Noble-gas notation: [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵.