# Zinc

Zinc, 30Zn|  |
| Zinc |
| Appearance | siller-gray |
| Standard atomic weight *A*r, 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 (*t*1/2) | 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 |
|

**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 (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.