Hassium

Hassium
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108 bohrium ← hassium → meitnerium
Os
↑
Hs
↓
(Upo)
Periodic Table - Extended Periodic Table


General
Name, Symbol, Number hassium, Hs, 108
Chemical series transition metals
Group, Period, Block 8, 7, d
Appearance unknown, probably silvery
white or metallic gray
Standard atomic weight (278)  g·mol−1
Electron configuration perhaps [Rn] 5f14 6d6 7s2
(guess based on osmium)
Electrons per shell 2, 8, 18, 32, 32, 14, 2
Physical properties
Phase presumably a solid
Atomic properties
Crystal structure hexagonic
Oxidation states 8, 7, 6, 5, 4, 3, 2, 1, −1
CAS registry number 54037-57-9
Selected isotopes
Main article: Isotopes of hassium iso NA half-life DM DE (MeV) DP
269Hs trace 14 s alpha
270Hs trace 22 s alpha

References
Hassium (IPA- /ˈhasiəm/), also called eka-osmium, is a synthetic element in the periodic table that has the symbol Hs and atomic number 108. Hassium oxidizes similar to osmium above it, to a hassium tetroxide with a lower volatility than osmium tetroxide.[1]

Contents [hide]
1 History
2 Hassium-270
3 References
4 External links



[edit] History
Hassium was first synthesized in 1984 by a German research team led by Peter Armbruster and Gottfried Münzenberg at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung) in Darmstadt. The name hassium was proposed by them, derived from the Latin name for the German state of Hesse where the institute is located.

There was an element naming controversy as to what the elements from 101 to 109 were to be called; thus IUPAC adopted unniloctium (IPA: /ˌjuːnɪlˈɒktiəm/, symbol Uno) as a temporary element name for this element. In 1994 a committee of IUPAC recommended that element 108 be named hahnium. The name hassium was adopted internationally in 1997.


[edit] Hassium-270
Isotope 270 of Hassium, discovered by an international team of scientists led by the Technical University of Munich in December 2006, is a doubly magic isotope with an unusually long half-life of 22 seconds. The existence of such relatively stable heavy isotopes had already been theoretically predicted, with some theories suggesting Hassium-270 may form part of an island of stability.[2]


[edit] References
^ "Chemistry of Hassium". Gesellschaft für Schwerionenforschung mbH (2002). Retrieved on 2007-01-31.
^ Mason Inman (2006-12-14). "A Nuclear Magic Trick". Physical Review Focus. Retrieved on 2006-12-25.

[edit] External links
WebElements.com - Hassium
Apsidium - Hs
Retrieved from "http://en.wikipedia.org/wiki/Hassium"
Categories: Chemical elements | Transition metals