Hassium (Hs)

Isotopes of Hassium 

Isotope Atomic Mass Half-life Mode of Decay Nuclear Spin Nuclear Magnetic Moment
Hs-263 263.1287 1.00 second α to Sg-259 No data available  No data available 
Hs-264 264.1284 0.00008 seconds α to Sg-260; SF No data available  No data available 
Hs-265 265.13016  0.0018 seconds α to Sg-261; SF No data available  No data available 
Hs-266 266.1300 0.033 seconds α decay No data available  No data available 
Hs-267 267.1318 52.00 milliseconds  α to Sg-263; SF No data available  No data available 
Hs-268 268.1321 0.40 seconds  α decay No data available  No data available 
Hs-269 269.1341 9.30 seconds α to Sg-265 No data available  No data available 
Hs-277 277 11.00 minutes No data available  No data available  No data available 

Hs

Hassium is a synthetic element (an element that can be created in a laboratory but is not found in nature), officially discovered in 1984 by a German research team led by Peter Armbruster and Gottfried Münzenberg at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung - GSI) in Darmstadt, Germany. The team bombarded a target of Lead-208 with accelerated nuclei of Iron-58 to produce three atoms of the isotope Hassium-265. More than 100 atoms of hassium have been synthesized to date. The name hassium derives from the Latin name (Hassia) for the German state of Hesse, where the institute is located.

The chemical properties of hassium are characterized only partly, but they compare well with the chemistry of the other group 8 elements. It is expected to be a silvery metal that reacts readily with oxygen in the air, forming a volatile tetroxide. It is predicted to be a solid at room temperature and to crystallize in the hexagonal close-packed structure. It is expected to be the densest element of the first seven periods.

Properties of Hassium

Name Hassium
Symbol Hs
Atomic number 108
Atomic weight [277] (status unclear)
Standard state Presumably a solid at 298 °K
CAS Registry ID 54037-57-9
Group in periodic table 8
Group name None
Period in periodic table 7
Block in periodic table d-block
Color Unknown, but probably metallic and silvery white or grey in appearance
Classification Metallic
Melting point No data available
Boiling point No data available
Density of solid 28.6 g/cm3 (predicted)
Electron configuration [Rn]5f146d67s2

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