Technetium: Difference between revisions
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All the isotopes of technetium are radioactive; 98 is the atomic mass of technetium's longest-lived isotope, <sup>98</sup>Tc (4.12x10<sup>6</sup>y).<ref>[http://periodictable.com/Isotopes/043.98/index.html Technetium Isotope data].</ref> Technetium is the lightest chemical element lacking a stable isotope. | All the isotopes of technetium are radioactive; 98 is the atomic mass of technetium's longest-lived isotope, <sup>98</sup>Tc (4.12x10<sup>6</sup>y).<ref>[http://periodictable.com/Isotopes/043.98/index.html Technetium Isotope data].</ref> Technetium is the lightest chemical element lacking a stable isotope. | ||
Only very small amounts of technetium are found in nature. Practically all technetium is produced synthetically as a by-product of the fission of [[Uranium|uranium-235]] in nuclear reactors and it is extracted from the spent reactor fuel rods.<ref>{{cite book|author=John Elmsley|title=Nature's Building Blocks: An A-Z Guide to the Elements|edition=1st Edition|publisher=Oxford University Press|year=2001|id=ISBN 0-19-850341-5}}</ref> | Only very small amounts of technetium are found in nature.<ref name=schwochau>Schwochau K. (2000) ''Technetium: chemistry and radiopharmaceutical applications''. Wiley-VCH. ISBN 9783527294961. | [http://books.google.com/books?id=BHjxH8q9iukC&dq=technetium&source=gbs_navlinks_s Google Books preview]. | ||
*<font face="Gill Sans MT">See section 3.2 for history of discovery of technetium in Earth's crust.</font></ref> Practically all technetium is produced synthetically as a by-product of the fission of [[Uranium|uranium-235]] in nuclear reactors and it is extracted from the spent reactor fuel rods.<ref>{{cite book|author=John Elmsley|title=Nature's Building Blocks: An A-Z Guide to the Elements|edition=1st Edition|publisher=Oxford University Press|year=2001|id=ISBN 0-19-850341-5}}</ref> | |||
==Technetium radioisotope half-lives== | ==Technetium radioisotope half-lives== | ||
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Technetium is a chemical element, having the chemical symbol Tc. Its atomic number (the number of protons) is 43. It has a standard atomic weight of 98.9062 g•mol −1 and is a solid in its elemental form.
Technetium is considered to be a member of the "Transition metal" class of elements.[1] At a pressure of 101.325 kPa, it has a boiling point of 4,265 °C and a melting point of 2,157 °C.
All the isotopes of technetium are radioactive; 98 is the atomic mass of technetium's longest-lived isotope, 98Tc (4.12x106y).[2] Technetium is the lightest chemical element lacking a stable isotope.
Only very small amounts of technetium are found in nature.[3] Practically all technetium is produced synthetically as a by-product of the fission of uranium-235 in nuclear reactors and it is extracted from the spent reactor fuel rods.[4]
Technetium radioisotope half-lives
References
- ↑ Note: Technitium is also sometimes referred to being a member of a Synthetic or Quasi-synthetic class of elements.
- ↑ Technetium Isotope data.
- ↑ Schwochau K. (2000) Technetium: chemistry and radiopharmaceutical applications. Wiley-VCH. ISBN 9783527294961. | Google Books preview.
- See section 3.2 for history of discovery of technetium in Earth's crust.
- ↑ John Elmsley (2001). Nature's Building Blocks: An A-Z Guide to the Elements, 1st Edition. Oxford University Press. ISBN 0-19-850341-5.