An Overview of the new Chemical Element Copernicium

It is not often that the scientific world gets a new chemical element. In June 2009, the International Union for Pure and Applied Chemistry (IUPAC) announced its official recognition of element 112. It fell to the discoverers of the element to decide on a new name. Now the element copernicium (symbol Cp) has been placed in the periodic table in position 112. It has been named after the astronomer Nicolaus Copernicus.

Anyone looking at an older version of the periodic table will see that there was an element already in this position, ununbium with symbol Uub. This was an IUPAC holding name for the element. When the claim for the discovery of a new element is made, it is given a holding name until the discovery is verified to the satisfaction of IUPAC. This system prevents an element having two different names if two groups of scientists find it at the same time.

The element now known as copernicium was discovered at 22:37 on 9 February 1996 in the laboratories at Gesellschaft fur Schwerionenforschung (GSI) in Darmstadt, Germany. A team of scientist under the leadership of Peter Armbruster and Gottfried Munzenber had been accelerating ions of the element zinc and firing them at a target of lead atoms. Eventually one of these collisions forced the two elements to combine to form an atom or two of a new super heavy element. Those first few atoms were the isotope copernicium-227 with a half-life of just 0.24 milliseconds.

Since that initial discovery, five isotopes of the element have been created. Copernicium-285 has the longest half-life at about ten minutes.

Man made elements such as copernicium are assigned the atomic mass of their longest-lived isotope. By this convention, the atomic mass of copernicium is 285 amu (atomic mass units). Not much else about the chemistry of copernicium is known. Insufficient atoms have been produced for any of its bulk properties, such as density or melting point, to be measured. From its position in the periodic table (d-block, group 12 and period 7) copernicium is a metallic element. The element should be white, gray or silver in color. It is unlikely that any quantity of this element will ever be made.

With one new element named there are a few others waiting for IUPAC to confirm their existence. Elements 113, 114, 115, 116 and 118 have all had claims made for their discovery. They all have temporary holding names under the IUPAC system.