4
Be
Beryllium
Alkaline earth metal period 2 group 2 s-block discovered: 1798
As a chemical element
Properties of the atom — they do not depend on what substance it is part of.
- Atomic number
- 4
- Atomic mass
- 9.012183 a.m.u.
- Electron configuration
- [He]2s2
- Electronegativity
- 1.57 on the Pauling scale
- Atomic radius
- 153 pm
- Ionization energy
- 9.323 eV
- Oxidation states
- +2
As a simple substance
Properties of the substance these atoms form under ordinary conditions.
- State at 25 °C
- Solid
- Melting point
- 1560 K (1 286,85 °C)
- Boiling point
- 2744 K (2 470,85 °C)
- Density
- 1.85 g/cm³