Boron (B)
Borum
Boron (B) is a metalloid in period 2, group 13. Its relative atomic mass is 10.81 and the molar mass of the atom is 10.81 g/mol.
Atomic number 5
Atomic mass 10.81
Molar mass 10.81 g/mol
Category Metalloid Solid
Properties of boron
| Atomic number | 5 |
|---|---|
| Symbol | B |
| Latin name | Borum |
| Relative atomic mass | 10.81 |
| Molar mass | 10.81 g/mol |
| Group, period, block | 13, 2, p |
| Category | Metalloid |
| State at 20 °C | Solid |
| Electron configuration | [He] 2s² 2p¹ |
| Electronegativity (Pauling) | 2.04 |
| Atomic radius | 85 pm |
Electron configuration of boron
Electrons per shell
K2L3
Full notation
1s² 2s² 2p¹
Noble-gas notation
5 protons · 5 electrons[He] 2s² 2p¹
Formula and compounds of boron
Simple substanceBboronMolar mass of B: 10.81 g/mol
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Frequently asked questions
The relative atomic mass of boron is 10.81, so the molar mass of the atom is 10.81 g/mol.
Full: 1s² 2s² 2p¹. Noble-gas notation: [He] 2s² 2p¹.