Symbol: Be
Atomic number: 4
Atomic mass: 9.012182
Group: Alkali Earth Metal
CAS-number: 7440-41-7

Physical data
Other info
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Li Lithium To Periodic Table BoronB

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Physical data

Electronic data

Shells: 2, 2
Orbitals: [He] 2s2
Electronegativity: 1.5, 1.5
1. Ionization potential: 9.3226 eV
2. Ionization potential: 18.211 eV
3. Ionization potential: 153.893 eV
Oxidation states: 2
Electrical conductivity: 0.313 10^6

Thermal data

Melting point: 1287 °C
Boiling point: 2472 °C
Specific heat: 1.82 J/gK
Heat of fusion: 12.20 kJ/mol
Heat of vaporization: 292.40 kJ/mol
Thermal conductivity: 2.00 W/cmK

Steric data

Atomic radius: 1.40 Å
Ionic radius: 0.45 Å (+2)
Covalent radius: 0.90 Å
Atomic volume: 5.0 cm³/mol
Density (293 K): 1.848 g/cm³
Crystal structure: hexagonal


NuclideAbundance [%]MassSpinHalflifeDecay modeDecay tree
7Be 0 7.0169 3/2 53.28d EC View
9Be 100 9.0122 3/2 -- --
10Be 0 10.0135 0 2.6E06y β- View

Other info

Name origin:Greek: beryllos, ""beryl"" (a mineral)
Description:Hard, brittle, steel-gray metal. Lightest rigid metal. Formerly called glucinium (Gl) for its sweet but deadly taste.
Discovered by:Fredrich Wöhler, A.A.Bussy
Sources:Found mostly in minerals like beryl [AlBe3(Si6O18)] and chrysoberyl (Al2BeO4). Pure beryllium is obtained by chemically reducing beryl mineral. Also by electrolysis of beryllium chloride.
Use(s):Its ability to absorb large amounts of heat makes it useful in spacecraft, missiles, aircraft, etc. Emeralds are beryl crystals with chromium traces giving them their green color.