technetium

tech·ne·ti·um   (těk-nē'shē-əm, -shəm)    n.   Symbol Tc A silvery-gray radioactive metal, the first synthetically produced element, having 14 isotopes with masses ranging from 92 to 105 and half-lives up to 4.2 × 106 years. It is used as a tracer and to eliminate corrosion in steel. Atomic number 43; melting point 2,200°C; specific gravity 11.50; valence 0, 2, 4, 5, 6, 7. See Table at element. [From Greek tekhnētos, artificial, from tekhnāsthai, to make by art, from tekhnē, art; see technical.]

Main Entry: tech·ne·tium
Pronunciation: tek-'nE-sh(E-)&m
Function: noun
: a metallic element that is obtained by bombarding molybdenum withdeuterons or neutrons and in the fission of uranium and that is used in medicine in the preparation of radiopharmaceuticals —symbol Tc; —see PERTECHNETATE; —ELEMENT table

technetium tech·ne·ti·um (těk-nē'shē-əm, -shəm)
n.
Symbol Tc
A radioactive metal, the first synthetically produced element, used as a tracer and to inhibit corrosion in steel. Atomic number 43; melting point 2,200°C; specific gravity 11.50; valence 0, 2, 4, 5, 6, 7.

technetium   (těk-nē'shē-əm)  Pronunciation Key  Symbol Tc A silvery-gray, radioactive metallic element. It was the first element to be artificially made, and it is produced naturally in extremely small amounts during the radioactive decay of uranium. Technetium is used to remove corrosion from steel. Its longest-lived isotope is Tc 98 with a half-life of 4,200,000 years. Atomic number 43; melting point 2,200°C; specific gravity 11.50; valence 0, 2, 4, 5, 6, 7. See Periodic Table.