Zinc

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).

Zinc, ₃₀Zn

Zinc
Appearance	siller-gray
Standard atomic weight Ar, std(Zn)	7001653800000000000♠65.38(2)
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 copper ← zinc → gallium
Atomic nummer (Z)	30
Group	group 12
Period	period 4
Block	d-block
Element category	Post-transeetion metal
Electron confeeguration	[Ar] 3d10 4s2
Electrons per shell	2, 8, 18, 2
Pheesical properties
Phase at STP	solit
Meltin pynt	692.68 K ​(419.53 °C, ​787.15 °F)
Bylin pynt	1180 K ​(907 °C, ​1665 °F)
Density (near r.t.)	7.14 g/cm3
when liquid (at m.p.)	6.57 g/cm3
Heat o fusion	7.32 kJ/mol
Heat o vapourisation	123.6 kJ/mol
Molar heat capacity	25.470 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)
Electronegativity	Pauling scale: 1.65
Ionisation energies	(more)
Atomic radius	empirical: 134 pm
Covalent radius	122±4 pm
Van der Waals radius	139 pm
Colour lines in a spectral range Spectral lines o zinc
Ither properties
Naitural occurrence	primordial
Creestal structur	​hexagonal close-packed (hcp)
Speed o soond thin rod	(rolled) 3850 m/s (at r.t.)
Thermal expansion	30.2 µm/(m·K) (at 25 °C)
Thermal conductivity	116 W/(m·K)
Electrical resistivity	59.0 n Ω·m (at 20 °C)
Magnetic orderin	diamagnetic
Young's modulus	108 GPa
Shear modulus	43 GPa
Bulk modulus	70 GPa
Poisson ratio	0.25
Mohs haurdness	2.5
Brinell haurdness	412 MPa
CAS Nummer	7440-66-6
History
Diskivery	Indian metallurgists (before 1000 BC)
First isolation	Andreas Sigismund Marggraf (1746)
Recognized as a unique metal bi	Rasaratna 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 (β−β−) 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

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 (Judea). 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. 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. 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. Zinc deficiency affects aboot twa billion fowk in the developin warld an is associated wi mony diseases. In childer, deficiency causes growthe retardation, delayed sexual maturation, infection susceptibility, an diarrhea. Enzymes wi a zinc atom in the reactive centre are widespread in biochemistry, sic as alcohol dehydrogenase in humans. Consumption o excess zinc can cause ataxia, lethargy an capper deficiency.