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Beryllium

المؤلف:  The University of Sheffield and WebElements Ltd, UK

المصدر:  The Periodic Table by WebElements

الجزء والصفحة:  ................

28-5-2017

1608

Beryllium

 

Beryllium is a Group 2 (IIA) element. It is a metal and has a high melting point. At ordinary temperatures, beryllium resists oxidation in air. Beryllium compounds are very toxic. Its ability to scratch glass is probably due to the formation of a thin layer of the oxide. Aquamarine and emerald are precious forms of the mineral beryl, [Be₃Al₂(SiO₃)₆].

Its chemistry is dominated by its tendency to lose an electron to form Be²⁺. As this ion is so small it is highly polarising, to the extent that its compounds are rather covalent. Its small size means that its complexes tend to be tetrahedral rahter than octahedral.

Beryllium was discovered by Nicholas Louis Vauquelin (1763-1829) in 1797 at France. Origin of name: from the Greek word "beryllos" meaning "beryl".Emeralds and beryl were both known to early Egyptians but it was not realised until the end of the 18th century that they are the same mineral, now called beryllium aluminium silicate: [Be₃Al₂(SiO₃)₆]. The element was recognised by M.-L. Vauquelin in 1798 in beryl and emeralds. The metal was isolated much later on in 1828 by Friederich Wöhler (and independently by A.-A.B. Bussy) by the action of potassium on BeCl₂ in a platinum crucible.  

In fact, compounds containing beryllium are poisonous. Beryllium is found in a number of minerals. The most important minerals are beryl, [Be₃Al₂(SiO₃)₆], which is often found as hexagonal prisms, and bertrandite [4BeO.2SiO₂.H₂O]. Aquamarine and emerald are precious forms of beryl.