Technetium

Description

An unstable radioactive element of the magnesium family. Technetium was the first artificially produced element in 1927. Carlo Perrier and Emilio Segre made technetium by the deuteron bombardment of molybdenum. Naturally occurring technetium is rare on earth, but in 1952, it was detected in the emission of S-type stars. It is used to increase corrosion resistance of steel and, in medicine, as a radioactive imaging agent for the liver.

Synonyms and Related Terms

Tc; masurium; technétium (Fr.); tecnezio (It.); tecnécio (Port.); tecnecio (Esp.); Teknetium (Sven.); Technetium (Deut., Ned.); technet (Pol.)

Other Properties

Dissolves in nitric acid, aqua regia, concentrated sulfuric acid

Composition	Tc (atomic no. 43)
CAS	7440-26-8
Melting Point	2200
Density	11.5
Molecular Weight	atomic wt = 98.9062

Additional Information

Web Elements: Website

Sources Checked for Data in Record

• Encyclopedia Britannica, http://www.britannica.com Comment: "technetium" Encyclopædia Britannica Premium Service. [Accessed 28 Sept. 2005].

• Chemical & Engineering News, American Chemical Society, Washington DC, 81 (36) , Sept. 8, 2003 Comment: John T. Armstrong, p. 110

• Wikipedia, the free encyclopedia, at http://www.wikipedia.com Comment: http://en.wikipedia.org/wiki/Technetium (Accessed Sept. 28, 2005)

• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 9286

• Website address 1 Comment: Web Elements at http://www.webelements.com/webelements/elements/text/Tc/key.html

• Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976

• 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