Editing Group 12 element (section)

==History==
The elements of group 12 have been found throughout history, being used since ancient times to being discovered in laboratories.  The group itself has not acquired a [[trivial name]], but it has been called ''group IIB'' in the past.

===Zinc===
Zinc has been found being used in impure forms in ancient times as well as in alloys such as brass that have been found to be over 2000 years old.{{sfn|Weeks|1933|p=20}}{{sfn|Greenwood|Earnshaw|1997|p=1201}} Zinc was distinctly recognized as a metal under the designation of ''Fasada'' in the medical Lexicon ascribed to the Hindu king Madanapala (of Taka dynasty) and written about the year 1374.<ref name="Ray1903">{{cite book |last=Ray|first=Prafulla Chandra|title=A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century, A.D.: With Sanskrit Texts, Variants, Translation and Illustrations |publisher=The Bengal Chemical & Pharmaceutical Works |year=1903|edition=2nd|volume=1|pages=157–158 |url=https://books.google.com/books?id=DL1HAAAAIAAJ}} (public domain text)</ref> The metal was also of use to [[Alchemy|alchemists]].<ref>{{Cite book|last=Arny|first=Henry Vinecome|title=Principles of Pharmacy|url=https://archive.org/details/principlespharm01arnygoog|publisher=W. B. Saunders company |year=1917|edition=2nd|page=[https://archive.org/details/principlespharm01arnygoog/page/n487 483]}}</ref> The name of the metal was first documented in the 16th century,<ref name="iza">{{cite web |last=Habashi|first=Fathi|title=Discovering the 8th Metal |publisher=International Zinc Association (IZA) |url=http://www.iza.com/Documents/Communications/Publications/History.pdf|access-date=2008-12-13|archive-url=https://web.archive.org/web/20090304154217/http://www.iza.com/Documents/Communications/Publications/History.pdf|archive-date=2009-03-04|url-status=dead}}</ref><ref>{{Cite book|title=Georgius Agricola de Re Metallica |first=Herbert Clark|last=Hoover|publisher=Kessinger Publishing|year=2003|page=409|isbn=978-0-7661-3197-2}}</ref> and is probably derived from the German {{lang|de|zinke}} for the needle-like appearance of metallic crystals.<ref>{{Cite book|title=Ullmann's Encyclopedia of Industrial Chemistry |last=Gerhartz|edition=5th|year=1996|isbn=978-3-527-20100-6 |publisher=VHC|page=509|first=Wolfgang}}</ref>

[[File:Zinc symbol (fixed width).svg|thumb|right|Alchemical symbol for the element zinc]]

The isolation of metallic zinc in the West may have been achieved independently by several people in the 17th century.{{sfn|Emsley|2001|p=502}} German chemist [[Andreas Sigismund Marggraf|Andreas Marggraf]] is usually given credit for discovering pure metallic zinc in a 1746 experiment by heating a mixture of [[calamine]] and charcoal in a closed vessel without copper to obtain a metal.{{sfn|Weeks|1933|p=21}} Experiments on frogs by the Italian doctor [[Luigi Galvani]] in 1780 with brass paved the way for the discovery of [[Battery (electricity)|electrical batteries]], galvanization and [[cathodic protection]].<ref name="ExcelPhysics">{{Cite book |title=Excel Preliminary Physics|last=Warren|first=Neville G.|publisher=Pascal Press|year=2000|page=47|isbn=978-1-74020-085-1|url=https://books.google.com/books?id=eL9Xn6nQ6XQC}}</ref><ref name=IntEncyl>{{Cite book |title=The New International Encyclopaedia|chapter=Galvanic Cell|page=80|year=1903|publisher=Dodd, Mead and Company|chapter-url=https://books.google.com/books?id=gV1MAAAAMAAJ&pg=PA80}}</ref> In 1799, Galvani's friend, [[Alessandro Volta]], invented the [[Voltaic pile]].<ref name="ExcelPhysics"/> The biological importance of zinc was not discovered until 1940 when [[carbonic anhydrase]], an enzyme that scrubs carbon dioxide from blood, was shown to have zinc in its [[active site]].{{sfn|Cotton|Wilkinson|Murillo|Bochmann|1999|p=626}}

===Cadmium===
In 1817, cadmium was discovered in Germany as an impurity in [[zinc carbonate]] minerals (calamine) by [[Friedrich Stromeyer]] and [[Karl Samuel Leberecht Hermann]].<ref>{{cite book|chapter = Cadmium |title = Kirk-Othmer Encyclopedia of Chemical Technology |edition = 4th |place=New York |publisher = John Wiley & Sons |year=1994 |volume= 5}}</ref> It was named after the Latin ''cadmia'' for "[[calamine]]", a cadmium-bearing mixture of minerals, which was in turn named after the Greek mythological character, Κάδμος [[Cadmus]], the founder of [[Ancient Thebes (Boeotia)|Thebes]].<ref>{{cite journal|journal = Annalen der Physik|year = 1818|pages = 113–116|volume = 59|title = Noch ein schreiben über das neue Metall (Another letter about the new metal)|author = Hermann|url = http://gallica.bnf.fr/ark:/12148/bpt6k150680/f125.chemindefer|bibcode = 1818AnP....59..113H |doi = 10.1002/andp.18180590511|issue = 5 }}</ref> Stromeyer eventually isolated cadmium metal by [[Roasting (metallurgy)|roasting]] and reduction of the [[cadmium sulfide|sulfide]].<ref>{{cite book|url = https://books.google.com/books?id=84VAAAAAYAAJ&pg=PA122|page = 122|title = Cyclopædia of commerce, mercantile law, finance, commercial geography and navigation|author1 = Waterston, William|author2 = Burton, J. H|year = 1844}}</ref><ref>{{cite book|url = https://books.google.com/books?id=Q-cHAAAAQAAJ&pg=PA10|page = 10|title = The art of landscape painting in water colours, by T. and T. L. Rowbotham|author1 = Rowbotham, Thomas Leeson|year = 1850}}</ref><ref name="Cadold">{{cite book|pages = 135–141|url = https://books.google.com/books?id=gGHOz1G3AqwC&pg=PA135|title = The life cycle of copper, its co-products and byproducts|isbn = 978-1-4020-1552-6|author1 = Ayres, Robert U.|author2 = Ayres, Leslie|author3 = Råde, Ingrid|year = 2003| publisher=Springer }}</ref>

In 1927, the [[Bureau International des Poids et Mesures|International Conference on Weights and Measures]] redefined the meter in terms of a red cadmium spectral line (1 m = 1,553,164.13 wavelengths).<ref>{{cite journal|title = On the new determination of the meter|journal = Measurement Techniques|volume = 1|issue = 3|year = 1958|doi = 10.1007/BF00974680|pages = 259–264|first= G. D.|last = Burdun| bibcode=1958MeasT...1..259B |s2cid = 121450003}}</ref> This definition has since been changed (see [[krypton]]). At the same time, the [[International Prototype Meter]] was used as standard for the length of a meter until 1960,<ref>{{cite journal |url=https://nvlpubs.nist.gov/nistpubs/jres/104/3/j43bee.pdf |title=The NIST Length Scale Interferometer |volume=104 |issue= 3 |date=May–June 1999 |journal=Journal of Research of the National Institute of Standards and Technology |first1=John S. |last1=Beers |first2=William B. |last2=Penzes |page=226|doi=10.6028/jres.104.017 |s2cid=2981956 }}</ref> when at the [[General Conference on Weights and Measures]] the meter was defined in terms of the orange-red [[emission line]] in the [[electromagnetic spectrum]] of the [[krypton]]-86 atom in [[vacuum]].<ref name=Marion>{{cite book|last=Marion|first=Jerry B.|title=Physics For Science and Engineering|year=1982|publisher=CBS College Publishing|isbn=978-4-8337-0098-6|page=3}}</ref>

===Mercury===
[[File:Mercury symbol.svg|thumb|right|120px|The symbol for [[Mercury (planet)|the planet Mercury]] (☿) has been used since ancient times to represent the element.]]

Mercury has been found in Egyptian tombs which have been dated back to 1500 BC,<ref>{{cite web|title=Mercury and the environment&nbsp;— Basic facts|publisher=[[Environment Canada]], Federal Government of Canada|year=2004|url=http://www.ec.gc.ca/MERCURY/EN/bf.cfm|access-date=2008-03-27|url-status=dead|archive-url=https://web.archive.org/web/20070115042236/http://www.ec.gc.ca/MERCURY/EN/bf.cfm|archive-date=2007-01-15}}</ref> where mercury was used in cosmetics. It was also used by the ancient Chinese who believed it would improve and prolong health.<ref>{{cite book|title=The History of China|year=2001|author=Wright, David Curtis|publisher=Greenwood Publishing Group|isbn=978-0-313-30940-3|page=[https://archive.org/details/historyofchina00wrig/page/49 49]|url=https://archive.org/details/historyofchina00wrig/page/49}}</ref> By 500 BC mercury was used to make [[amalgam (chemistry)|amalgams]] (Medieval Latin amalgama, "alloy of mercury") with other metals.<ref>{{cite book|url=https://books.google.com/books?id=DIWEi5Hg93gC&pg=PA120|page=120|title=Jewelrymaking through history|author=Hesse, R. W.|publisher=Greenwood Publishing Group|year= 2007|isbn=978-0-313-33507-5}}</ref> [[Alchemy|Alchemists]] thought of mercury as the [[Prima materia|First Matter]] from which all metals were formed. They believed that different metals could be produced by varying the quality and quantity of [[sulfur]] contained within the mercury. The purest of these was gold, and mercury was called for in attempts at the [[wiktionary:Transmutation|transmutation]] of base (or impure) metals into gold, which was the goal of many alchemists.<ref name="Stillman">{{cite book|title = Story of Alchemy and Early Chemistry|author = Stillman, J. M.|publisher = Kessinger Publishing|year = 2003|isbn = 978-0-7661-3230-6|pages = 7–9|url = https://books.google.com/books?id=hdaAGF5Y1N0C}}{{Dead link|date=May 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

Hg is the modern [[chemical symbol]] for mercury. It comes from ''hydrargyrum'', a [[Latin]]ized form of the [[Greek language|Greek]] word Ύδραργυρος (''hydrargyros''), which is a compound word meaning "water-silver" (hydr- = water, argyros = silver)&nbsp;— since it is liquid like water and shiny like silver. The element was named after the Roman god [[Mercury (mythology)|Mercury]], known for speed and mobility. It is associated with the planet [[Mercury (planet)|Mercury]]; the astrological symbol for the planet is also one of the [[alchemical symbol]]s for the metal.<ref>{{cite book|url=https://books.google.com/books?id=ykEN2zHvCpQC&pg=PA260|page=260|title=The Pillar of Celestial Fire|author=Cox, R.|publisher=1st World Publishing|year= 1997|isbn=978-1-887472-30-2}}</ref> Mercury is the only metal for which the alchemical planetary name became the common name.<ref name="Stillman"/>

===Copernicium===
The heaviest known group 12 element, copernicium, was [[discovery of the chemical elements|first created]] on February 9, 1996, at the [[Gesellschaft für Schwerionenforschung]] (GSI) in [[Darmstadt]], Germany, by Sigurd Hofmann, [[Victor Ninov]] et al.<ref name="Hoffman">{{Cite journal|title=The new element 112 |journal=[[Zeitschrift für Physik A]]|author=Hofmann, S.|volume=354|issue=1|year=1996|pages=229–230 |doi=10.1007/BF02769517 |display-authors=etal |bibcode=1996ZPhyA.354..229H|s2cid=119975957}}</ref> It was then officially named by the [[International Union of Pure and Applied Chemistry]] (IUPAC) after [[Nicolaus Copernicus]] on February 19, 2010, the 537th anniversary of Copernicus' birth.<ref>{{cite journal |title=Element 112 is Named Copernicium |doi=10.1351/PAC-REP-08-03-05 |last1=Barber |first1=Robert C. |last2=Gäggeler |first2=Heinz W. |last3=Karol |first3=Paul J. |last4=Nakahara |first4=Hiromichi |last5=Vardaci |first5=Emanuele |last6=Vogt |first6=Erich |journal=Pure and Applied Chemistry |volume=81 |issue=7 |pages=1331–1343 |year=2009 |doi-access=free }}</ref>