Chemical Element: ununnilium

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Chemical-Element Information

Symbol: Uun
Atomic number: 110
Year discovered: 1994

Discovered by: Sigurd Hofmann, Victor Ninov, F. P. Hessberger, P. Armbruster, H. Folger, G. Münzenberg, H. J. Schött, and others; at Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany.

• On the 9th of November 1994 at 4:39 P.M. (16:39 hours) the first atom of element 110 was detected at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany.
• The isotope discovered has an atomic number of 269 (that is, 269 times heavier than hydrogen).
• Chemically, the element 110 is in the same Group as nickel, palladium, and platinum (Group 10). Unlike these lighter atoms, element 110 decays after a small fraction of a thousandth of a second into lighter elements by emitting a-particles that are the nuclei of helium atoms.
• The new element was produced by fusing a nickel and a lead atom together. This was achieved by accelerating the nickel atoms to a high energy in the heavy ion accelerator UNILAC at GSI.
• Over a period of many days, many billion billion nickel atoms were fired at a lead target in order to produce and identify a single atom of element 110.
• The element 110 was the fourth element discovered at GSI between 1981 and 1984.
• The elements 107 (bohrium), 108 (hassium), 109 (meitnerium) were all produced and identified there.
• Since the discovery of element 110, elements 111 and 112 were also discovered at GSI.
• See ununnilium (Uub), Atomic Number 112, for further data.

Name in other languages:

French: ununnilium

German: Ununnilium

Italian: ununnilio

Spanish: ununnilio

Information about other elements may be seen at this Chemical Elements List.

A special unit about words that include chemo-, chem- may be seen here.