Americium (Am)
Americium
Americium (Am) is an actinide in period 7. Its relative atomic mass is [243] and the molar mass of the atom is [243] g/mol.
Atomic number 95
Atomic mass [243] predicted
Molar mass [243] g/mol
Category Actinide Solid
Properties of americium
| Atomic number | 95 |
|---|---|
| Symbol | Am |
| Latin name | Americium |
| Relative atomic mass | [243] |
| Molar mass | [243] g/mol |
| Group, period, block | —, 7, f |
| Category | Actinide |
| State at 20 °C | Solid |
| Electron configuration | [Rn] 5f⁷ 7s² |
| Electronegativity (Pauling) | 1.13 |
| Atomic radius | 175 pm |
Electron configuration of americium
Electrons per shell
K2L8M18N32O25P8Q2
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁷ 6s² 6p⁶ 7s²
Noble-gas notation
95 protons · 95 electrons[Rn] 5f⁷ 7s²
Formula and compounds of americium
Simple substanceAmamericiumMolar mass of Am: [243] g/mol
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Frequently asked questions
The relative atomic mass of americium is [243], so the molar mass of the atom is [243] g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁷ 6s² 6p⁶ 7s². Noble-gas notation: [Rn] 5f⁷ 7s².