copernicium, artificially produced radioactive chemical element; symbol Cn; at. no. 112; mass number of most stable isotope 285; m.p., b.p., sp. gr., and valence unknown. Situated in Group 12 of the periodic table, it is expected to have properties similar to those of zinc, cadmium, and mercury.
In 1996 an international research team led by Peter Armbruster and Sigurd Hofmann at the Institute for Heavy Ion Research at Darmstadt, Germany bombarded lead-208 atoms with high-energy zinc-70 ions. In a two-week experiment, one of the resultant atoms was unambiguously identified as an isotope of element 112 with mass number 277 and a half-life of 280 msec. Copernicium was initially called ununbium, from the Latin roots un for one and bi for two, under a convention for neutral temporary names proposed by the International Union of Pure and Applied Chemistry (IUPAC) in 1980. In 2009 the name copernicium, for Copernicus, was proposed for the element by its discoverers, and IUPAC approved the name in 2010. The most stable isotope, copernicium-285, has a half-life of approximately 29 sec.
See also synthetic elements; transactinide elements; transuranium elements.
"copernicium." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (January 24, 2019). https://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/copernicium
"copernicium." The Columbia Encyclopedia, 6th ed.. . Retrieved January 24, 2019 from Encyclopedia.com: https://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/copernicium
Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).
Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.
Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:
Modern Language Association
The Chicago Manual of Style
American Psychological Association
- Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
- In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.