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Atomic Number: 4
Atomic Symbol: Be
Atomic Weight: 9.01218
Electron Configuration: [He]2s2
History
(Gr. beryllos, beryl; also called Glucinium or Glucinum, Gr. glykys,
sweet) Discovered as the oxide by Vauquelin in beryl and in emeralds in 1798.
The metal was isolated in 1828 by Wohler and by Bussy independently by the
action of potassium on beryllium chloride.
Sources
Beryllium is found in some 30 mineral species, the most important of
which are bertrandite, beryl, chrysoberyl, and phenacite. Aquamarine and emerald
are precious forms of beryl. Beryl and bertrandite are the most important
commercial sources of the element and its compounds. Most of the metal is now
prepared by reducing beryllium fluoride with magnesium metal. Beryllium metal
did not become readily available to industry until 1957.
Properties
The metal, steel gray in color, has many desirable properties. As one
of the lightest of all metals, it has one of the highest melting points of the
light metals. Its modulus of elasticity is about one third greater than that of
steel. It resists attack by concentrated nitric acid, has excellent thermal
conductivity, and is nonmagnetic. It has a high permeability to X-rays and when
bombarded by alpha particles, as from radium or polonium, neutrons are produced
in the amount of about 30 neutrons/million alpha particles.
At ordinary temperatures, beryllium resists oxidation in air,
although its ability to scratch glass is probably due to the formation of a thin
layer of the oxide.
Uses
Beryllium is used as an alloying agent in producing beryllium copper,
which is extensively used for springs, electrical contacts, spot-welding
electrodes, and non-sparking tools. It is applied as a structural material for
high-speed aircraft, missiles, spacecraft, and communication satellites. Other
uses include windshield frame, brake discs, support beams, and other structural
components of the space shuttle.
Because beryllium is relatively transparent to X-rays,
ultra-thin Be-foil is finding use in X-ray lithography for reproduction of
microminiature integrated circuits.
Beryllium is used in nuclear reactors as a reflector or
moderator for it has a low thermal neutron absorption cross section.
It is used in gyroscopes, computer parts, and instruments where
lightness, stiffness, and dimensional stability are required. The oxide has a
very high melting point and is also used in nuclear work and ceramic
applications.
Handling
Beryllium and its salts are toxic and should be handled with the
greatest of care. Beryllium and its compounds should not be tasted to verify the
sweetish nature of beryllium (as did early experimenters). The metal, its
alloys, and its salts can be handled if certain work codes are observed, but no
attempt should be made to work with beryllium before becoming familiar with
proper safeguards.
Sources: CRC Handbook of Chemistry and
Physics and the American Chemical Society.
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