Periodic Table of Elements

108

Hassium

277.15

Hassium was discovered by Peter Armbruster and Gottfried Münzenberg at the Institute for Heavy Ion Research at Darmstadt, Germany in 1984.

Name: Hassium
Symbol: Hs
Atomic number: 108
Atomic weight: 277.15
State: solid presumably
Group, period, block: 8, 7, d
Color: unknown
Classification: transition metal
Electron configuration: 5f14 6d6 7s2
2,8,18,32,32,14,2

Physical properties

Density: 41 g/cm-3
Melting point: no data
Boiling point: no data

Atomic properties

Oxidation states: 8, 6, 4, 3
Electronegativity: no data
Ionization energies: 1st: 733.3 kJ·mol-1
Covalent radius: 134 pm
Van der Waals radius: no data
  • Hs
  • Electron Configuration

Isotopes

Hassium is an artificial element, and thus a standard atomic mass cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 265Hs in 1984. There are 12 known isotopes from 263Hs to 277Hs and 1-4 isomers. The longest-lived isotope is 269Hs with a half-life of 9.6 seconds.