Be
Atomic Number - 4
Beryllium has a very high melting point at 2349° F (1287°C).
The History Says
The name beryllium is derived from the Greek word 'beryllos,' beryl. Even some time in past, beryllium was referred to as glucinium due to the sweet taste of its salts. In Greek sweet is said as 'glykys.'
The Present Scenario
Beryllium did not become readily available until 1957. Presently, most production of this metal is accomplished by reducing beryllium fluoride with magnesium metal.
BERYLLIUM IS the chemical element with atomic number as 4. It is a toxic bivalent element. It is steel grey, strong, light-weight but brittle and alkaline earth metal. It is used as a hardening agent in alloys, usually beryllium copper.
Of all the metals, beryllium has one of the highest melting point. Its modulus of elasticity is approximately 1/3 greater than steel. It is nonmagnetic, resists attack by concentrated nitric acid, is an excellent thermal conductivity and it is highly permeable to X-rays. At a standard temperature and pressure it resists oxidation when exposed to air.
Physical Properties of Beryllium
| Phase | Solid |
| Density (near room temperature) | 1.85 g/cm3 |
| Liquid density at melting point | 1.690 g/cm3 |
| Melting point | 1560 K (1287°C, 4476°F) |
| Boiling point | 2742 K (2469°C, 4476°F) |
| Heat of fusion | 7.895 kJ/mol |
| Heat of vaporization | 297 kJ/mol |
| Heat capacity | (25°C) 16.443 J/(mol-K) |
Atomic Properties of Beryllium
| Crystal structure | Hexagonal |
| Oxidation states | 2 (amphoteric oxide) |
| Electronegativity | 1.57 (Pauling scale) |
| Ionization energies | 1st: 8995 kJ/mol 2nd: 1757.1 kJ/mol 3rd: 14848.7 kJ/mol |
| Atomic radius | 105 pm |
| Atomic radius | 112 pm |
| Covalent radius | 90 pm |
Uses of Beryllium
- As an alloying agent in the production of beryllium copper.
- Sheets of beryllium foil are used with X-ray detection diagnostics.
- For the reproduction of microscopic integrated circuits in the field of X-ray lithography.
- As a neutron reflector and moderator in nuclear reactors.
- In nuclear weapons to surround the plutonium sphere which reduces the mass of the sphere.
- In neutron sources where it is mixed with an alpha emmiter like polonium 210, radium 226, or actinium 227.
- In the making of gyroscopes, various computer equipment, watch springs and instruments that requires light-weight, rigidity and dimensional stability.
- It is also required in those applications where an excellent head condutor, with high strength and hardness and with a very high melting point is needed. Even it should act as an electrical insulator.
- Once used in fluorescent lighting tubes.
Precautions with Beryllium
Both beryllium and its salts are toxic substances. Exposure to it may cause a pulmonary and systemic granulomatous disease called chronic berylliosis. This disease was first described in 1946 among the workers of fluorescent lamps manufacturing plant in Massachusetts.
Lung cancer can be a result of prolonged exposure to beryllium laden dust. So handling of beryllium should be with great care. Earlier researchers use to taste beryllium and its various compounds for the sweetness in order to verify its presence. Modern diagnostic equipment no longer necessitates this. No attempt should be made to ingest this substance.
Substitutes and Alternative Sources of Beryllium
Graphite, steel and titanium is used in some applications for beryllium. But, beryllium is a critical component of many military and aerospace applications, and though it is expensive to produce, costing more than silver, it is not often replaced by other materials.