Neptunium (Np)
Neptunium
Neptunium (Np) is an actinide in period 7. Its relative atomic mass is [237] and the molar mass of the atom is [237] g/mol.
Atomic number 93
Atomic mass [237] predicted
Molar mass [237] g/mol
Category Actinide Solid
Properties of neptunium
| Atomic number | 93 |
|---|---|
| Symbol | Np |
| Latin name | Neptunium |
| Relative atomic mass | [237] |
| Molar mass | [237] g/mol |
| Group, period, block | —, 7, f |
| Category | Actinide |
| State at 20 °C | Solid |
| Electron configuration | [Rn] 5f⁴ 6d¹ 7s² |
| Electronegativity (Pauling) | 1.36 |
| Atomic radius | 175 pm |
Electron configuration of neptunium
Electrons per shell
K2L8M18N32O22P9Q2
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁴ 6s² 6p⁶ 6d¹ 7s²
Noble-gas notation
93 protons · 93 electrons[Rn] 5f⁴ 6d¹ 7s²
Formula and compounds of neptunium
Simple substanceNpneptuniumMolar mass of Np: [237] g/mol
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Frequently asked questions
The relative atomic mass of neptunium is [237], so the molar mass of the atom is [237] g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁴ 6s² 6p⁶ 6d¹ 7s². Noble-gas notation: [Rn] 5f⁴ 6d¹ 7s².