Boron

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  • Topic: Boron, Humphry Davy, Boric acid
  • Pages : 4 (1094 words )
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  • Published : March 20, 2013
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Boron Element Facts

Amorphous Boron in sample-tube. (Photo by Tomihahndorf)
5B10.81
Data Zone
Classification:| Boron is a metalloid|
Color:| black|
Atomic weight:| 10.81|
State:| solid|
Melting point:| 2075 oC, 2348 K|
Boiling point:| 3727 oC , 4000 K|
Electrons:| 5|
Protons:| 5|
Neutrons in most abundant isotope:| 6|
Electron shells:| 2,3|
Electron configuration:| 1s2 2s2 2p1|
Density @ 20oC:| 2.34 g/cm3|

Show more, including: Heats, Energies, Oxidation, Reactions, Compounds, Radii, Conductivities Discovery of Boron
Dr. Doug Stewart
Boron compounds such as borax (sodium tetra borate, Na2B4O7·10H2O) have been known and used by ancient cultures for thousands of years. Borax’s name comes from the Arabic buraq, meaning “white.” Boron was first partially isolated in 1808 by French chemists Joseph L. Gay-Lussac and L. J. Thénard and independently by Sir Humphry Davy in London. Gay-Lussac & Thénard reacted boric acid with magnesium or sodium to yield boron, a gray solid. (1) They believed it shared characteristics with sulfur and phosphorus and named it bore. (2) Davy first tried to produce boron by electrolysis of boric acid, but was not satisfied with the results. He enjoyed greater success reacting boric acid with potassium in a hydrogen atmosphere. The result was a powdery substance.

Davy commented the substance was, “of the darkest shades of olive. It is opake, very friable, and its powder does not scratch glass.” After carrying out a number of chemical reactions to verify the uniqueness of the substance, Davy wrote, “there is strong reason to consider the boracic basis as metallic in nature, and I venture to propose for it the name of boracium.” (2) Neither party had, in fact, produced pure boron. Their samples were only about 60% pure. In 1909, American chemist Ezekiel Weintraub was able to produce 99% pure boron, by reducing boron halides with hydrogen. Almost a century later, in 2004, Jiuhua Chen...
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