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Oxidation & Electrons | Appearance & Characteristics Reactions | Compounds | Radius | Conductivity Abundance & Isotopes 
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General:
| Name: Beryllium | Symbol: Be |
| Type: Alkali Earth Metal | Atomic weight: 9.01218 |
| Density @ 293 K: 1.848 g/cm3 | Atomic volume: 4.9 cm3/mol |
| Discovered: Discovered in the oxide form by Vauquelin in both beryl and emeralds in 1798. Elemental beryllium was isolated in 1828 by Friederich Wöhler by the action of potassium on beryllium chloride in a platinum crucible. | |
States
| State (s, l, g): solid | |
| Melting point: 1551.2 K (1278 oC) | Boiling point: 2742 K (2469 oC) |
Energies
| Specific heat capacity: 1.82 J g-1 K-1 | Heat of atomization: 324 kJ mol-1 |
| Heat of fusion: 7.895 kJ mol-1 | Heat of vaporization (sublimation): 297 kJ mol-1 |
| 1st ionization energy: 899.5 kJ mol-1 | 2nd ionization energy: 1757.1 kJ mol-1 |
| 3rd ionization energy: 14848.7 kJ mol-1 | Electron affinity: 0 kJ mol-1 |
Oxidation & Electrons
| Shells: 2,2 | Electron configuration: [He] 2d2 |
| Minimum oxidation number: 0 | Maximum oxidation number: 2 |
| Min. common oxidation no.: 0 | Max. common oxidation no.: 2 |
| Electronegativity (Pauling Scale): 1.57 | Polarizability volume: 5.6 Å3 |
Appearance & Characteristics
| Structure: hcp: hexagonal close packed | Color: steel gray |
| Harmful effects: Beryllium and its salts are both toxic and carcinogenic. | Hardness: 5.5 mohs |
| Characteristics: The surface of beryllium metal is covered with a thin layer of oxide that helps protect the metal from attack by water or air. It does not oxidize in air even at 600oC. Beryllium resists attack by concentrated nitric acid, has excellent thermal conductivity, and is nonmagnetic. | |
| Uses: Beryllium is used for X-ray windows. Beryllium alloys are used as a light-weight structural material for high-speed aircraft, missiles, spacecraft, and communication satellites. Beryllium is also used in nuclear reactors as a reflector or moderator. | |
Reactions
| Reaction with air: vigourous, w/ht ⇒ BeO, Be3N2 | Reaction with 6 M HCl: mild ⇒ H2 |
| Reaction with 15 M HNO3: none | Reaction with 6 M NaOH: mild ⇒ H2, [Be(OH)4]2 |
Compounds
| Oxide(s): BeO3 | Chloride(s): BeCl2 |
| Hydride(s): BeH2 |
Radius
| Atomic radius: 112 pm | Ionic radius (1+ ion): pm |
| Ionic radius (2+ ion): 45 pm | Ionic radius (3+ ion): pm |
| Ionic radius (2- ion): pm | Ionic radius (1- ion): pm |
Conductivity
| Thermal conductivity: 200 W m-1 K-1 | Electrical conductivity: 0.25 x 10-6 S cm-1 |
Abundance & Isotopes
| Abundance earth's crust: 1.9 ppm by weight, 4.3 ppm by moles | |
| Abundance solar system: 0.1 parts per billion by weight, 0.01 parts per billion by moles | |
| Cost, pure: 530 $/100g | |
| Cost, bulk: 59 $/100g | |
| Source: The mineral beryl, [Be3Al2(SiO3)6] is the most important source of beryllium. | |
| Isotopes: 9 isotopes with known half-lives. 9Be is the only stable isotope. Cosmogenic 10Be (half-life 1.51 million years) is produced in the atmosphere by the impact of cosmic rays on oxygen and nitrogen. | |
