Boron
Metalloid
Boron (B) is a chemical element with atomic number 5, classified as a metalloid. At room temperature it is a solid. It was discovered in 1808 by Joseph Louis Gay-Lussac, Louis Jacques Thénard.
Properties
- Atomic number
- 5
- Atomic mass
- 10.81 u
- Category
- Metalloid
- Group
- 13
- Period
- 2
- Block
- p-block
- Electron configuration
- [He] 2s² 2p¹
- Phase at STP
- Solid
- Density
- 2.34 g/cm³
- Melting point
- 2349 K (2075.8 °C)
- Boiling point
- 4200 K (3926.8 °C)
- Electronegativity
- 2.04
- Atomic radius
- 87 pm
- Ionization energy
- 8.298 eV
- Discovery
- 1808 · Joseph Louis Gay-Lussac, Louis Jacques Thénard
Common uses
Glass manufacturing, fertilizers, nuclear control rods
Did you know?
Essential for plant growth and found in household borax cleaning products.