Hassium

2007 Schools Wikipedia Selection. Related subjects: Chemical elements

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
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.

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 (language) 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.