Tantalum
Description
A bluish-gray metallic element. Tantalum was recognized as an element by Anders Ekeberg, a Swedish chemist, in 1802 but not isolated as a pure metal until 1907 by von Bolton. It occurs in nature with niobium in minerals such as columbite, tantalite, and microlite and is mined primarily in western Australia, Manitoba and South Dakota. Tantalum is a hard, ductile metal that can be drawn into thin wires. Tantalum is used to make lightbulb filaments, electronic capacitors, pen nibs, surgical instruments, sutures and pins in broken bones. Tantalum oxide is used to make a high quality glass for telescope and camera lenses.
Synonyms and Related Terms
Ta; Tantaal (Ned.); tantale (Fr.); Tantal (Deut., Sven., Pol.); tantalio (It.); Tântalo (Port.); tántalo (Esp.)
Other Properties
Resistant to acids, ammonium hydroxide, sea water, chloride salts and sulfurous atmospheres.
Composition | Ta (atomic no. 73) |
---|---|
CAS | 7440-25-7 |
Mohs Hardness | 6.5 |
Melting Point | 2996 |
Density | 14.5-16.6 |
Molecular Weight | atomic wt = 180.9479 |
Refractive Index | 2.05 |
Boiling Point | 5425-5427 |
Hazards and Safety
Dust or powder may be flammable. Toxic by inhalation.
Sigma Chemical: MSDS
Additional Information
Web Elements: Website
Authority
- G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 798
- Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976 Comment: pure form of tantalum made by Berzelius in 1820
- The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 9223; discovered by Ekeberg in 1802 and first purified by Bolton
- Encyclopedia Britannica, http://www.britannica.com Comment: "tantalum" Encyclopædia Britannica Premium Service. [Accessed 28 Sept. 2005].
- Website address 1 Comment: Web Elements at http://www.webelements.com/webelements/elements/text/Ta/hist.html states discovered by Ekeberg in 1802 and von Bolton first purified tantalum in 1907
- Chemical & Engineering News, American Chemical Society, Washington DC, 81 (36) , Sept. 8, 2003 Comment: Richard Schrock, p. 140: discovered in 1802 by Swedish chemist Anders Gustav Ekeberg
- Wikipedia, the free encyclopedia, at http://www.wikipedia.com Comment: http://en.wikipedia.org/wiki/Tantalum (Accessed Sept. 28, 2005)
- Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998