Antimony (Sb)
Stibium
Antimony (Sb) is a metalloid in period 5, group 15. Its relative atomic mass is 121.76 and the molar mass of the atom is 121.76 g/mol.
Atomic number 51
Atomic mass 121.76
Molar mass 121.76 g/mol
Category Metalloid Solid
Properties of antimony
| Atomic number | 51 |
|---|---|
| Symbol | Sb |
| Latin name | Stibium |
| Relative atomic mass | 121.76 |
| Molar mass | 121.76 g/mol |
| Group, period, block | 15, 5, p |
| Category | Metalloid |
| State at 20 °C | Solid |
| Electron configuration | [Kr] 4d¹⁰ 5s² 5p³ |
| Electronegativity (Pauling) | 2.05 |
| Atomic radius | 145 pm |
Electron configuration of antimony
Electrons per shell
K2L8M18N18O5
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³
Noble-gas notation
51 protons · 51 electrons[Kr] 4d¹⁰ 5s² 5p³
Formula and compounds of antimony
Simple substanceSbantimonyMolar mass of Sb: 121.76 g/mol
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Frequently asked questions
The relative atomic mass of antimony is 121.76, so the molar mass of the atom is 121.76 g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p³. Noble-gas notation: [Kr] 4d¹⁰ 5s² 5p³.