Manganese

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Manganese,  25Mn
A fragment o lustrous sillery metal
General properties
Appearancesilvery metallic
Staundart atomic wecht (Ar, staundart)54.938043(2)[1]
Manganese 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
-

Mn

Tc
chromiummanganeseiron
Atomic nummer (Z)25
Groupgroup 7
Periodperiod 4
Element category  transition metal
Blockd-block
Electron confeeguration[Ar] 4s2 3d5
Electrons per shell
2, 8, 13, 2
Pheesical properties
Phase (at STP)solit
Meltin pynt1519 K ​(1246 °C, ​2275 °F)
Bylin pynt2334 K ​(2061 °C, ​3742 °F)
Density (near r.t.)7.21 g/cm3
when liquid (at m.p.)5.95 g/cm3
Heat o fusion12.91 kJ/mol
Heat o vapourisation221 kJ/mol
Molar heat capacity26.32 J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1228 1347 1493 1691 1955 2333
Atomic properties
Oxidation states7, 6, 5, 4, 3, 2, 1, -1, -2, -3 ​oxides: acidic, basic or amphoteric; depending on the oxidation state
ElectronegativityPauling scale: 1.55
Ionisation energies
Atomic radiusempirical: 127 pm
Covalent radius139±5 (low spin), 161±8 (high spin) pm
Coloyr lines in a spectral range
Spectral lines o Manganese
Miscellanea
Creestal structurbody-centred cubic (bcc)
Body-centered cubic creestal structur for manganese
Speed o soond thin rod5150 m/s (at 20 °C)
Thermal expansion21.7 µm/(m·K) (at 25 °C)
Thermal conductivity7.81 W/(m·K)
Electrical resistivity1.44 µ Ω·m (at 20 °C)
Magnetic orderinparamagnetic
Young's modulus198 GPa
Bouk modulus120 GPa
Mohs haurdness6.0
Brinell haurdness196 MPa
CAS Nummer7439-96-5
History
DiskiveryTorbern Olof Bergman (1770)
First isolationJohann Gottlieb Gahn (1774)
Main isotopes o manganese
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct 52Mn syn 5.591 d ε 52Cr
β+ 52Cr
γ -
53Mn trace 3.74×106 y ε 53Cr
54Mn syn 312.3 d ε 54Cr
γ -
55Mn 100% stable
| references | in Wikidata

Manganese is a chemical element, designated bi the seembol Mn. It haes the atomic nummer 25. It is foond as a free element in naitur (eften in combination wi iron), an in mony meenerals. Manganese is a metal wi important industrial metal alloy uises, parteecularly in stainless steels.

Historically, manganese is named for pyrolusite an ither black meenerals frae the region o Magnesia in Greece, that an aw gae its name tae magnesium an the airn ure magnetite. Bi the mid-18th century, Swadish-German chemist Carl Wilhelm Scheele haed uised pyrolusite tae produce chlorine. Scheele an ithers war awaur that pyrolusite (nou kent tae be manganese dioxide) conteened a new element, but thay war unable tae isolate it. Johan Gottlieb Gahn wis the first tae isolate an impure saumple o manganese metal in 1774, that he did bi reducin the dioxide wi caurbon.

Manganese phosphating is uised for roust an corrosion prevention on steel. Ionised manganese is uised industrially as pigments o various colours, that depend on the oxidation state o the ions. The permanganates o alkali an alkaline yird metals are pouerfu oxidisers. Manganese dioxide is uised as the cathode (electron acceptor) material in zinc-carbon an alkaline batteries.

In biology, manganese(II) ions function as cofactors for a lairge variety o enzymes wi mony functions.[2] Manganese enzymes are pairteecularly essential in detoxification o superoxide free radicals in organisms that maun deal wi elemental oxygen. Manganese an aw functions in the oxygen-evolvin complex o photosynthetic plants. While the element is a required trace meeneral for aw kent leevin organisms, it an aw acts as a neurotoxin in lairger amoonts. Espeicially throu inhalation, it can cause manganism, a condeetion in mammals leadin tae neurological damage that is whiles irreversible.

References[eedit | eedit soorce]

  1. Meija, J.; 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. Roth, Jerome; Ponzoni, Silvia; Aschner, Michael (2013). "Chapter 6 Manganese Homeostasis and Transport". In Banci, Lucia. Metallomics and the Cell. Metal Ions in Life Sciences. 12. Springer. doi:10.1007/978-94-007-5561-1_6. ISBN 978-94-007-5560-4.  electronic-book ISBN 978-94-007-5561-1