Beryllium
Grey metallic element of group 2 of the periodic table. Is toxic and can cause severe lung diseases and dermatitis. Shows high covalent character. It was isolated independently by F. Wohler and A.A. Bussy in 1828.
Gallery
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Physical Propertiesmass · density · phase · crystal
Atomic Mass
9.0122Da
Density
1.8500g/cm³
Phase (STP)
Solid
Melting Point
1560.2K
Boiling Point
2741.2K
Molar Heat
1.8250J/(mol·K)
Crystal Structure
HEX
Lattice Constant
2.290Å
Atomic Radiiatomic · covalent · van der Waals
Atomic (Empirical)
105.00pm
Covalent
102.00pm
Van der Waals
153.00pm
Electronic Propertieselectronegativity · ionization · affinity
Electron Configuration
[He] 2s2
Electron Shells
2, 2
Electronegativity
1.57Pauling
Electron Affinity
-2.4kJ/mol
1st Ionization Energy
9.3kJ/mol
Oxidation States
+2
Ionization Energies (4 known)
Emission Spectrumvisible range · characteristic spectral lines
Abundanceby mass
Log scale · ppm = parts per million by mass
Biological Role
Highly toxic. Beryllium dust causes chronic beryllium disease (berylliosis).
Discovery
Discovered By
Fredrich Wöhler, A.A.Bussy
Named By
—
Year
1798
Nuclear Data
Known Isotopes
12
Stable Isotopes
1
Stable Mass Numbers
9
Natural isotopic abundance (IUPAC recommended values)
Isotopes of Be12 known
| Nuclide | Z | N | Mass (AMU) | Half-life | Decay | Jπ | Abundance |
|---|---|---|---|---|---|---|---|
| 5Be | 4 | 1 | 5.039870 | Unknown | p | 1/2+ | — |
| 6Be | 4 | 2 | 6.019726 | 5.00 zs | 2p (1%) | 0+ | — |
| 7Be | 4 | 3 | 7.016929 | 53.2 d | EC (1%) | 3/2- | — |
| 9Bestable | 4 | 5 | 9.012183 | Stable | stable (1%) | 3/2- | 10000.0000% |
| 14Be | 4 | 10 | 14.042893 | 4.53 ms | β⁻ (1%), β⁻n (0.86%), 2n (0.05%), B-t (0.0002%), β⁻α (0.00004%) | 0+ | — |
| 15Be | 4 | 11 | 15.053490 | Unknown | n (1%) | 5/2+ | — |
| 16Be | 4 | 12 | 16.061672 | Unknown | 2n (1%) | 0+ | — |