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Bismuth is a chemical element in the periodic table that has the symbol Bi and atomic number 83. This is heavy, brittle, white crystalline trivalent true metal that has a pink tinge and chemically resembles arsenic and antimony. Most diamagnetic of all metals, bismuth has the lowest thermal conductivity of all the elements except mercury. Lead-free bismuth compounds are used in cosmetics and in medical procedures.
Table of contents |
2 Applications 3 History 4 Occurrence 5 External Links |
Before 2003, Bismuth was thought to be the heaviest stable element, however research at the Institut d'Astrophysique Spatiale in Orsay, France calculated the alpha emission half-life of the metal to be (1.9 +/- 0.2) × 1019 years (meaning it is not a stable element). It is a brittle metal with a pinkish hue with an iridescent tarnish. Among the heavy metalss, it is the heaviest and the only non-toxic. No other metal is more diamagnetic than bismuth, except mercury. This metal, which occurs in its native form, has a high electrical resistance and also has the highest Hall effect of any metal (that is, it has the greatest increase in electrical resistance when it is placed in a magnetic field). When heated in air bismuth burns with a blue flame and its oxide forms yellow fumes.
Bismuth oxychloride is extensively used in cosmetics and bismuth subnitrate and subcarbonate are used in medicine. Other uses;
"Bismanol" (MnBiBi) is a strong permanent magnet.
Notable Characteristics
Applications
In the early 1990s, research began on the evaluation of bismuth as a nontoxic replacement for lead in such uses as ceramic glazes, fishing sinkers, food processing equipment, free-machining brasses for plumbing applications, lubricating greases, and shot for waterfowl hunting.
History
Bismuth (German Weisse Masse meaning "white mass"; later Wisuth and Bisemutum) was confused in early times with tin and lead due to its resemblance to those elements. In 1753 Claude Geoffroy Junine showed that this metal is distinct from lead.
Occurrence
Bismuthinite and bismite are the most important ores of bismuth. Canada, Bolivia, Japan, Mexico, and Peru are major producers. Bismuth produced in the United States is obtained as a by-product of copper, gold, lead, silver, tin and especially lead ore processing. The average price for bismuth in 2000 was US 3.50 per pound.