Darmstadtium

2007 Schools Wikipedia Selection. Related subjects: Chemical elements

110 meitnerium ← darmstadtium → roentgenium
Pt
↑
Ds
↓
(Uhn)
Periodic Table - Extended Periodic Table
General
Name, Symbol, Number darmstadtium, Ds, 110
Chemical series transition metals
Group, Period, Block 10, 7, d
Appearance unknown, probably silvery
white or metallic gray
Atomic mass (282) g/mol
Electron configuration perhaps [Rn] 5f14 6d9 7s1
(in analogy to platinum)
Electrons per shell 2, 8, 18, 32, 32, 17, 1
Phase presumably a solid
CAS registry number 54083-77-1
References

Darmstadtium ( IPA: /ˌdɑːmˈʃtatiəm/), formerly called ununnilium ( IPA: /ˌjuːnuːˈnɪliəm/, symbol Uun) or eka-platinum, is a chemical element with the symbol Ds and atomic number 110. It is one of the so-called super-heavy atoms. This synthetic element quickly decays: its isotopes of mass 267 to 273 have half-lives measured in microseconds. Heavier isotopes, of mass 279 and 281, have been subsequently synthesized and are more stable, with half-lives of 180 milliseconds and 11.1 seconds, respectively.

History

Ds was first generated on November 9, 1994 at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany by a team headed by Dr. Jorge Rigol. Only a few atoms of it were prepared by nuclear fusion, involving bombarding a lead target with nickel:

{208 \atop 82}\mathrm{Pb}+{62 \atop 28}\mathrm{Ni}\quad\rightarrow\quad{269 \atop 110}\mathrm{Ds}+{1 \atop 0}\mathrm{n} \;

The element was named after the place of its discovery, Darmstadt (the GSI is located in Wixhausen, a northern portion of the city). The new name was given to it by the IUPAC on August 16, 2003.

Trivia

Some suggested (for fun) the name policium for the new element, because 110 is the emergency telephone number for the German police.

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