Boron
Boron (硼, symbol B) is chemical element number 5, a Metalloid in period 2, group 13 of the periodic table, with a standard atomic weight of about 10.81. Metalloid essential to plants. Compounds used in glass, ceramics, and detergents.
Properties
| Atomic number | 5 |
|---|---|
| Symbol | B |
| Atomic mass | 10.81 u |
| Category | Metalloid |
| Period | 2 |
| Group | 13 |
| Electron configuration | [He] 2s² 2p¹ |
| Electronegativity | 2.04 |
| Covalent radius | 84 pm |
| Density | 2.34 g/cm³ |
| Melting point | 2349 K |
| Boiling point | 4200 K |
| Discovery | Gay-Lussac & Thénard, 1808 |
Overview
Metalloid essential to plants. Compounds used in glass, ceramics, and detergents. Element 5, Boron (B), is a Metalloid found in period 2, group 13. As a metalloid it shares properties of both metals and nonmetals and is a mainstay of semiconductor materials.
Its electron configuration is [He] 2s² 2p¹, with 3 electrons in the outer shell, and an electronegativity of about 2.04 (Pauling). Around 25 °C it is usually a solid (a very high melting point); it melts near 2349 K (2075.9 °C), boils near 4200 K (3926.9 °C), has a density around 2.34 g/cm³.
In industry and daily life it turns up in Agriculture / Fertiliser and Structural / Alloys. It was first described by Gay-Lussac & Thénard in 1808. Browse elements of the same category in the browse view.
Electron shells
Electrons per shell: 2 · 3
Main uses
- Agriculture / Fertiliser
- Structural / Alloys
Hazard
Compounds containing Boron
No compounds in this knowledge base contain Boron yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.