Hassium

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
Atomic mass (278) g/mol
Electron configuration perhaps [Rn] 5f14 6d6 7s2
(guess based on osmium)
Electrons per shell 2, 8, 18, 32, 32, 14, 2
Phase presumably a solid
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. It is predicted that hassium will be the densest element yet known, with a density exceeding two and a half times that of lead. This assumes that a measurable quantity of the element can be made, which is not possible at this time.

Contents
[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 Hessen 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, systematic 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.[1]

[edit]

References

  1. ↑ Mason Inman (2006-12-14). "A Nuclear Magic Trick". Physical Review Focus. Retrieved on 2006-12-25.
[edit]

External links

Retrieved from "http://localhost../../../art/a/2/e.html"
This text comes from Wikipedia the free encyclopedia. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. For a complete list of contributors for a given article, visit the corresponding entry on the English Wikipedia and click on "History" . For more details about the license of an image, visit the corresponding entry on the English Wikipedia and click on the picture.
WikipediaOnDVD is developed by Linterweb