Discovery date : 1984
Discovered by: Peter Armbruster, Gottfried Münzenberg
Origin of the name: The name is derived from the German state of Hesse where Hassium was first made.
Allotropes :
~>HASSIUM is a synthetic chemical element with symbol Hs and atomic number 108. It is named after the German state of Hesse. It is a synthetic element and radioactive; the most stable known isotope, 77Hs, has a half-life of approximately 30 seconds.
| FACT BOX | |||
| Group | 8 | Melting point | Unknown |
| Period | 7 | Boiling point | Unknown |
| Block | d | Density (g cm−3) | Unknown |
| Atomic number | 108 | Relative atomic mass | [269] |
| State at 20°C | Solid | Key isotopes | 270Hs |
| Electron configuration | [Rn] 5f146d67s2 | CAS number | 54037-57-9 |
| ChemSpider ID | - | ChemSpider is a free chemical structure database | |
There are 15 known isotopes of hassium with mass numbers 263 to 277, with isotope-276 having the longest half-life of 1.1 hour. The first attempt to synthesize element 108 took place in 1978 at Russia’s Joint Institute for Nuclear Research (JINR) in Dubna, where a team headed by Yuri Oganessian and Vladimir Utyonkov bombarded radium with calcium and got isotope 270. In 1983, they obtained other isotopes: by bombarding bismuth with manganese they got isotope 263, by bombarding californium with neon they got isotope 270, and by bombarding lead with iron they got isotope 264.
In 1984, at Germany’s Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, a team headed by Peter Armbruster and Gottfried Münzenberg bombarded lead with iron and synthesised isotope 265. Their data which was considered more reliable than that from JINR and so they were allowed to name the element which they did, basing it on Hesse, the state in which the GSI is located.