Discovered By: Joseph Louis Gay-Lussac, Louis-Jacques Thenard, Humphry Davy.
Discovery year: 1808.
| Symbol | B |
| Atomic number | 5 |
| Atomic weight | 10.81 |
| oxidation states | +3 |
| Electrons per shell | K2 L3 |
| Atomic radius | 87 picometer |
| Covalent radius | 84 picometer |
| Boiling point | 4000°C |
| Melting point | 2075°C |
| Electron configuration | 1s^2 2s^2 2p^1 |
| Group | 13 |
| Block | p |
| Period | 2 |
| Electrons | 5 |
| Protons | 5 |
| Neutrons | 6 |
| Phase | Solid |
| Crystal structure | rhombohedral |
| Fusion heat | 50.2 kJ/mol |
| Heat of Vaporization | 508 kJ/mol |
| Color | Black |
| Density (at melting point) | 2.08 g/cm^3 |
| Bulk modulus | 320 GPa |
| Mohs hardness | 9.3 |
| Sound speed | 16,200 m/s (at 20°C) |
| Thermal conductivity | 27.4 W/(m-K) |
| Vickers hardness | 49000 MPa |
| Electric type | Insulator |
| Magnetic type | Diamagnetic |
| Electromagnetivity | 2.04 |
| Valence | 3 |
| Radioactive | No |


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