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1992-09-30
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883b
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21 lines
BORON
Atomic symbol - B
Atomic weight - 10.811
Atomic number - 5
Electron configuration - 2-3
Oxidation states - +3
State of matter - solid
Non-metal
Discovered in 1808 by Joseph Louis Gay-Lussac and Louis-Jacques Thènard
Boils at 2550 °C, melts at 2300 °C
Notes:
Boron is relativally rare, and is never found free, it's always found combined
with oxygen in borates. The most important source of it is borax, or sodium
tetraborate, found in the desert regions of California. Boric acid, another
compound, is found in the volcanic regions of Italy. Boron is very hard and
brittle, and is found in two allotropic forms, crystalline and amorphous.
Boron is used in flares to give off a green color, it's used as an igniter in
rockets, as filaments in aerospace structures, and in silicon semiconductors
to improve conductivity.