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Zinc

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Zinc, 30Zn
Template:Infobox element/symbol-to-top-image/alt
Zinc
Appearancesiller-gray
Standard atomic weight Ar, std(Zn)65.38(2)[1]
Zinc in the periodic cairt
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gowd Mercur (element) Thallium Leid (element) Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium
-

Zn

Cd
copperzincgallium
Atomic nummer (Z)30
Groupgroup 12
Periodperiod 4
Blockd-block
Element category  Post-transeetion metal
Electron confeeguration[Ar] 3d10 4s2
Electrons per shell2, 8, 18, 2
Pheesical properties
Phase at STPsolit
Meltin pynt692.68 K ​(419.53 °C, ​787.15 °F)
Bylin pynt1180 K ​(907 °C, ​1665 °F)
Density (near r.t.)7.14 g/cm3
when liquid (at m.p.)6.57 g/cm3
Heat o fusion7.32 kJ/mol
Heat o vapourisation123.6 kJ/mol
Molar heat capacity25.470 J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 610 670 750 852 990 1179
Atomic properties
Oxidation states−2, 0, +1, +2 (an amphoteric oxide)
ElectronegativityPauling scale: 1.65
Ionisation energies
Atomic radiusempirical: 134 pm
Covalent radius122±4 pm
Van der Waals radius139 pm
Colour lines in a spectral range
Colour lines in a spectral range
Spectral lines o zinc
Ither properties
Naitural occurrenceprimordial
Creestal structurhexagonal close-packed (hcp)
Hexagonal close packed creestal structur for zinc
Speed o soond thin rod(rolled) 3850 m/s (at r.t.)
Thermal expansion30.2 µm/(m·K) (at 25 °C)
Thermal conductivity116 W/(m·K)
Electrical resistivity59.0 n Ω·m (at 20 °C)
Magnetic orderindiamagnetic
Young's modulus108 GPa
Shear modulus43 GPa
Bulk modulus70 GPa
Poisson ratio0.25
Mohs haurdness2.5
Brinell haurdness412 MPa
CAS Nummer7440-66-6
History
DiskiveryIndian metallurgists (before 1000 BC)
First isolationAndreas Sigismund Marggraf (1746)
Recognized as a unique metal biRasaratna Samuccaya (800)
Main isotopes o zinc
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct
64Zn 48.6% >2.3×1018 y (β+β+) 64Ni
65Zn syn 243.8 d ε 65Cu
γ -
66Zn 27.9% stable
67Zn 4.1% stable
68Zn 18.8% stable
69Zn syn 56 min β 69Ga
69mZn syn 13.76 h β 69Ga
70Zn 0.6% >1.3×1016 y (ββ) 70Ge
71Zn syn 2.4 min β 71Ga
71mZn syn 3.97 d β 71Ga
72Zn syn 46.5 h β 72Ga
Decay modes in parentheses are predictit, but hae nae yet been observed
| references

Zinc is a chemical element wi the seembol Zn an atomic nummer 30. It is the first element in group 12 o the periodic table. In some respects zinc is chemically seemilar tae magnesium: baith elements exhibit anly ane normal oxidation state (+2), an the Zn2+ an Mg2+ ions are o seemilar size. Zinc is the 24t maist abundant element in Yird's crust an haes five stable isotopes. The maist common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The lairgest workable lodes are in Australie, Asia, an the United States. Zinc is refined bi froth flotation o the ore, roasting, an final extraction uisin electricity (electrowinning).

Bress, an alloy o capper an zinc in various proportions, wis uised as early as the third millennium BC in the Aegean, Iraq, the Unitit Arab Emirates, Kalmykia, Turkmenistan an Georgia, an the seicont millennium BC in West India, Uzbekistan, Iran, Sirie, Iraq, an Israel[2] (Judea[3]).[4] Zinc metal wis nae produced on a lairge scale until the 12t century in India an wis unkent tae Europe until the end o the 16t century. The mines o Rajasthan hae gien definite evidence o zinc production going back tae the 6t century BC.[5] Tae date, the auldest evidence o pure zinc comes frae Zawar, in Rajasthan, as early as the 9t century AD when a distillation process wis employed tae mak pure zinc.[6] Alchemists burned zinc in air tae form what thay cried "philosopher's wool" or "white snow".

The element wis probably named bi the alchemist Paracelsus efter the German wird Zinke (prong, tuith). German chemist Andreas Sigismund Marggraf is credited wi discovering pure metallic zinc in 1746. Wirk bi Luigi Galvani an Alessandro Volta uncovered the electrochemical properties o zinc bi 1800. Corrosion-reseestant zinc plating o iron (het-dip galvanisin) is the major application for zinc. Ither applications are in electrical batteries, smaw non-structural castins, an alloys sic as bress. A variety o zinc compoonds are commonly uised, sic as zinc carbonate an zinc gluconate (as dietary supplements), zinc chloride (in deodorants), zinc pyrithione (anti-fousk shampoos), zinc sulfide (in luminescent paints), an zinc methyl or zinc diethyl in the organic laboratory.

Zinc is an essential meeneral perceived bi the public the day as bein o "exceptional biologic and public health importance", especially regarding prenatal an postnatal development.[7] Zinc deficiency affects aboot twa billion fowk in the developin warld an is associated wi mony diseases.[8] In childer, deficiency causes growthe retardation, delayed sexual maturation, infection susceptibility, an diarrhea.[7] Enzymes wi a zinc atom in the reactive centre are widespread in biochemistry, sic as alcohol dehydrogenase in humans.[9] Consumption o excess zinc can cause ataxia, lethargy an capper deficiency.

References

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  1. Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
  2. Thornton, C. P. (2007). "Of brass and bronze in prehistoric Southwest Asia" (PDF). Papers and Lectures Online. Archetype Publications. ISBN 1-904982-19-0.
  3. Greenwood 1997, p. 1201
  4. Craddock, Paul T. (1978). "The composition of copper alloys used by the Greek, Etruscan and Roman civilizations. The origins and early use of brass". Journal of Archaeological Science. 5 (1): 1–16. doi:10.1016/0305-4403(78)90015-8.
  5. "India Was the First to Smelt Zinc by Distillation Process". Infinityfoundation.com. Retrieved 25 Apryle 2014.
  6. Kharakwal, J. S. & Gurjar, L. K. (1 December 2006). "Zinc and Brass in Archaeological Perspective". Ancient Asia. 1: 139–159. doi:10.5334/aa.06112. Archived frae the original on 3 December 2013. Retrieved 12 Mey 2017. Cite uses deprecated parameter |last-author-amp= (help)
  7. a b Hambidge, K. M. & Krebs, N. F. (2007). "Zinc deficiency: a special challenge". J. Nutr. 137 (4): 1101–5. PMID 17374687. Cite uses deprecated parameter |last-author-amp= (help)
  8. Prasad, A. S. (2003). "Zinc deficiency : Has been known of for 40 years but ignored by global health organisations". British Medical Journal. 326 (7386): 409–10. doi:10.1136/bmj.326.7386.409. PMC 1125304. PMID 12595353.
  9. Maret, Wolfgang (2013). "Chapter 14 Zinc and the Zinc Proteome". In Banci, Lucia (ed.). Metallomics and the Cell. Metal Ions in Life Sciences. 12. Springer. doi:10.1007/978-94-007-5561-10_14. ISBN 978-94-007-5561-1.