Editing Copernicium (section)

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{{Infobox copernicium}}
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'''Copernicium''' is a [[synthetic element|synthetic chemical element]]; it has [[Chemical symbol|symbol]] '''Cn''' and [[atomic number]] 112. Its known isotopes are extremely [[radioactive]], and have only been created in a laboratory. The most stable known [[isotope]], copernicium-285, has a [[half-life]] of approximately 30 seconds. Copernicium was first created in February 1996 by the [[GSI Helmholtz Centre for Heavy Ion Research]] near [[Darmstadt]], Germany. It was named after the astronomer [[Nicolaus Copernicus]] on his 537th anniversary.<!-- Please do not add nationality here, as this much-debated issue is not relevant to this article. Please refer to the [[Nicolaus Copernicus]] article instead -->

In the [[periodic table (standard)|periodic table]] of the elements, copernicium is a [[d-block]] [[transactinide element]] and a [[group 12 element]]. During reactions with [[gold]], it has been shown<ref name="07Ei01">
{{cite journal
|last1=Eichler |first1=R.
|year=2007
|title=Chemical Characterization of Element 112
|journal=[[Nature (journal)|Nature]]
|volume=447 |issue=7140 |pages=72–75
|bibcode=2007Natur.447...72E
|doi=10.1038/nature05761
|pmid=17476264
|s2cid=4347419
|display-authors=etal}}</ref> to be an extremely volatile element, so much so that it is possibly a gas or a volatile liquid at [[standard temperature and pressure]].

Copernicium is calculated to have several properties that differ from its lighter [[Homologous series|homologues]] in group 12, [[zinc]], [[cadmium]] and [[mercury (element)|mercury]]; due to [[Relativistic quantum chemistry|relativistic effects]], it may give up its 6d electrons instead of its 7s ones, and it may have more similarities to the [[noble gas]]es such as [[radon]] rather than its group 12 homologues. Calculations indicate that copernicium may show the [[oxidation state]] +4, while mercury shows it in [[mercury(IV) fluoride|only one compound]] of disputed existence and zinc and cadmium do not show it at all. It has also been predicted to be more difficult to oxidize copernicium from its neutral state than the other group 12 elements. Predictions vary on whether solid copernicium would be a metal, semiconductor, or insulator. Copernicium is one of the heaviest elements whose chemical properties have been experimentally investigated.