Copernicium (Cn), artificially produced transuranium element of atomic number 112. In 1996 scientists at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung [GSI]) in Darmstadt, Ger., announced the production of atoms of copernicium from fusing zinc-70 with lead-208. The atoms of copernicium had an atomic weight of 277 and decayed after 0.24 millisecond by emission of an alpha particle (helium nucleus) to darmstadtium-273. Several other isotopes of copernicium are known; the longest lasting, isotope 285, has a half-life of 34 seconds. Its chemical properties may be similar to those of mercury. In June 2009 the discovery of element 112 by the GSI was recognized by the International Union of Pure and Applied Chemistry (IUPAC). The discoverers named it copernicium, after Polish astronomer Nicolaus Copernicus, in July 2009, and IUPAC approved that name in February 2010. Continue reading from Encyclopedia Britannica
Copernicium was created and identified on Feb. 9, 1996, by a team led by Peter Armbruster and Gottfried Münzenber at the Gesellschaft fur Schwerionenforschung lab in Darmstadt, Germany. They produced atoms of 277 Cn. Continue reading from LiveScience
Copernicium is named for Nicolaus Copernicus, the famed astronomer and mathematician. The symbol Cp was initially recommended for element 112, but was rejected because Cp had once been used as the symbol for lutetium, which, prior to 1949, was sometimes called cassiopeium. Copernicium is a radioactive, synthetic element about which little is known. It is classified as a metal and is expected to be solid at room temperature. Its properties are somewhat similar to radon, but its short half-life makes it difficult to study. Copernicium has four isotopes whose half-lives are known. The most stable isotope is 285Cn, with a half-life of about 30 seconds. It decays through alpha decay. The atomic weight for manmade transuranium elements is based on the longest-lived isotope. These atomic weights should be considered provisional since a new isotope with a longer half-life could be produced in the future. Continue reading from LiveScience
