4 Be 9.012

Beryllium

Alkaline Earth Metal

Beryllium (Be) is a chemical element with atomic number 4, classified as a alkaline earth metal. At room temperature it is a solid. It was discovered in 1798 by Louis Nicolas Vauquelin.

Properties

Atomic number
4
Atomic mass
9.012 u
Category
Alkaline Earth Metal
Group
2
Period
2
Block
s-block
Electron configuration
[He] 2s²
Phase at STP
Solid
Density
1.85 g/cm³
Melting point
1560 K (1286.8 °C)
Boiling point
2742 K (2468.8 °C)
Electronegativity
1.57
Atomic radius
112 pm
Ionization energy
9.323 eV
Discovery
1798 · Louis Nicolas Vauquelin

Common uses

Aerospace alloys, X-ray windows, nuclear reactors

Did you know?

Extremely toxic but incredibly strong and lightweight - used in spacecraft.