Editing Group 12 element (section)

===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}}