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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: Beryllium was discovered by Louis-Nicholas Vauquelin in 1798. Vauquelin found beryllia (BeO) in emeralds and in the mineral beryl (beryllium aluminum cyclosilicate). Beryllium was first isolated by Friederich Wöhler in 1828. Wöhler reacted potassium with beryllium chloride in a platinum crucible yielding potassium chloride and beryllium. | |
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: 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 |
| Hardness: 5.5 mohs | |
(Photo: Alchemist-hp) |
Harmful effects: Beryllium and its salts are both toxic and carcinogenic. Characteristics: Beryllium has the highest melting point of the light metals, melting at 1278 oC - considerably higher than, for example, Lithium (180 oC) Sodium (98 oC) Magnesium (650 oC) Aluminum (660 oC) or Calcium (839 oC). On the surface of beryllium a thin layer of the hard oxide BeO forms, protecting the metal from further attack by water or air. As a result of the BeO layer, beryllium does not oxidize in air even at 600oC and it resists corrosion by concentrated nitric acid. Beryllium also has high thermal conductivity and is nonmagnetic. Uses: Unlike most metals, beryllium is virtually transparent to x-rays and hence it is used in radiation windows for x-ray tubes. Beryllium alloys are used in the aerospace industry as light-weight materials for high performance aircraft, satellites and spacecraft. Beryllium is also used in nuclear reactors as a reflector and absorber of neutrons, a shield and a 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: 2.8 parts per million by weight, 4.6 parts per million by moles | |
| Abundance solar system: parts per billion by weight, parts per billion by moles | |
| Cost, pure: $ per 100g | |
| Cost, bulk: $ per 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. | |
