Element Zinc, Zn, Transition Metal
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Zinc History
Humanity was familiar with the manufacture of brass from ancient ages. However the metal zinc was not was known. Instead of it Phrygian ash, used for healing sore eyes, was mentioned in the Ebers papyrus from about 1552 BC, the oldest preserved medical document. Brass is known probably since 2 century BC. In Europe it is produced since year 1400 AD. Smelting and extraction of metal zinc was accomplished perhaps since XII century AD in India. Several hypotheses exist about the origin of the name "zinc". Some of scientists suppose that it may also be derived from Persian sing for stone. A Lexicon of Alchemy by Martin Ruland (Martinus Rulandus the Elder) defines zinc as metallic marcasite, a mixture of four elements. By another, less credible version the name derives from ancient or medieval German Zinco or Zinke = sharp point. Some suppose a relation with Zinn, the German word for Tin.
Zinc belongs to the Transition metals family.
Zinc Occurrence
Average crustal abundance of zinc is 8.3x10-3 mass %. In basic igneous rocks its abundance slightly bigger than in the acidic ones: 1.3x10-2% vs. 6x10-3%. This chalcophilic element is, nevertheless, found in 66 rocks, the most important of them are zincite, sphalerite, willemite, calamine, smithsonite and franklinite ZnFe2O4. Zinc is a very active aquatic migrant, especially in thermal waters with accompanied by Lead from which commercially important zinc sulphides are settled out. Zinc actively migrates also in surface and underground waters, settled out by H2S or, in a less degree, by clay sorption.
Zinc is an essential element, necessary for sustaining all life. A grown-up human body contains 2 g of zinc. Despite zinc-containing enzymes are omnipresent, its actual concentration is so small, that its importance was fully understood only 100 years ago. Its significant role is based on the fact that zinc may be found in more than 40 essential enzymes. It catalyzes hydrolysis peptides, proteins, some esters and aldehydes. The most important of them are carboxypeptidase A and carbonic anhydrase.
Zinc contributes to carbohydrate metabolism via insulin and activates vitamin A in the organism. It plays noticeable role for bone formation as well as for its antivirus and antitoxic activity.
Zinc Neighbours
Element Periodic Table | |