Manganese

  • manganese, 25mn
    a rough fragment of lustrous silvery metal
    manganese
    pronunciationz/ (mang-gə-neez)
    appearancesilvery metallic
    standard atomic weight ar, std(mn)54.938043(2)[1]
    manganese in the periodic table
    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 iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton
    rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver 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 gold mercury (element) thallium lead 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 nihonium flerovium moscovium livermorium tennessine oganesson


    mn

    tc
    chromiummanganeseiron
    atomic number (z)25
    groupgroup 7
    periodperiod 4
    blockd-block
    element category  transition metal
    electron configuration[ar] 3d5 4s2
    electrons per shell2, 8, 13, 2
    physical properties
    phase at stpsolid
    melting point1519 k ​(1246 °c, ​2275 °f)
    boiling point2334 k ​(2061 °c, ​3742 °f)
    density (near r.t.)7.21 g/cm3
    when liquid (at m.p.)5.95 g/cm3
    heat of fusion12.91 kj/mol
    heat of vaporization221 kj/mol
    molar heat capacity26.32 j/(mol·k)
    vapor pressure
    p (pa) 1 10 100 1 k 10 k 100 k
    at t (k) 1228 1347 1493 1691 1955 2333
    atomic properties
    oxidation states−3, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7 (depending on the oxidation state, an acidic, basic, or amphoteric oxide)
    electronegativitypauling scale: 1.55
    ionization energies
    • 1st: 717.3 kj/mol
    • 2nd: 1509.0 kj/mol
    • 3rd: 3248 kj/mol
    • (more)
    atomic radiusempirical: 127 pm
    covalent radiuslow spin: 139±5 pm
    high spin: 161±8 pm
    color lines in a spectral range
    spectral lines of manganese
    other properties
    natural occurrenceprimordial
    crystal structurebody-centered cubic (bcc)
    body-centered cubic crystal structure for manganese
    speed of sound 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 µΩ·m (at 20 °c)
    magnetic orderingparamagnetic
    magnetic susceptibility(α) +529.0·10−6 cm3/mol (293 k)[2]
    young's modulus198 gpa
    bulk modulus120 gpa
    mohs hardness6.0
    brinell hardness196 mpa
    cas number7439-96-5
    history
    discoverycarl wilhelm scheele (1774)
    first isolationjohann gottlieb gahn (1774)
    main isotopes of manganese
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    52mn syn 5.6 d ε 52cr
    β+ 52cr
    γ
    53mn trace 3.74×106 y ε 53cr
    54mn syn 312.03 d ε 54cr
    γ
    55mn 100% stable
    category category: manganese
    | references

    manganese is a chemical element with the symbol mn and atomic number 25. it is not found as a free element in nature; it is often found in minerals in combination with iron. manganese is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels.

    historically, manganese is named for pyrolusite and other black minerals from the region of magnesia in greece, which also gave its name to magnesium and the iron ore magnetite. by the mid-18th century, swedish-german chemist carl wilhelm scheele had used pyrolusite to produce chlorine. scheele and others were aware that pyrolusite (now known to be manganese dioxide) contained a new element, but they were unable to isolate it. johan gottlieb gahn was the first to isolate an impure sample of manganese metal in 1774, which he did by reducing the dioxide with carbon.

    manganese phosphating is used for rust and corrosion prevention on steel. ionized manganese is used industrially as pigments of various colors, which depend on the oxidation state of the ions. the permanganates of alkali and alkaline earth metals are powerful oxidizers. manganese dioxide is used as the cathode (electron acceptor) material in zinc-carbon and alkaline batteries.

    in biology, manganese(ii) ions function as cofactors for a large variety of enzymes with many functions.[3] manganese enzymes are particularly essential in detoxification of superoxide free radicals in organisms that must deal with elemental oxygen. manganese also functions in the oxygen-evolving complex of photosynthetic plants. while the element is a required trace mineral for all known living organisms, it also acts as a neurotoxin in larger amounts. especially through inhalation, it can cause manganism, a condition in mammals leading to neurological damage that is sometimes irreversible.

  • characteristics
  • history
  • occurrence and production
  • applications
  • biological role
  • precautions
  • environmental health concerns
  • role in neurological disorders
  • see also
  • references
  • external links

Manganese, 25Mn
A rough fragment of lustrous silvery metal
Manganese
Pronunciationz/ (MANG-gə-neez)
Appearancesilvery metallic
Standard atomic weight Ar, std(Mn)54.938043(2)[1]
Manganese in the periodic table
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 Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver 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 Gold Mercury (element) Thallium Lead 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 Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


Mn

Tc
chromiummanganeseiron
Atomic number (Z)25
Groupgroup 7
Periodperiod 4
Blockd-block
Element category  Transition metal
Electron configuration[Ar] 3d5 4s2
Electrons per shell2, 8, 13, 2
Physical properties
Phase at STPsolid
Melting point1519 K ​(1246 °C, ​2275 °F)
Boiling point2334 K ​(2061 °C, ​3742 °F)
Density (near r.t.)7.21 g/cm3
when liquid (at m.p.)5.95 g/cm3
Heat of fusion12.91 kJ/mol
Heat of vaporization221 kJ/mol
Molar heat capacity26.32 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1228 1347 1493 1691 1955 2333
Atomic properties
Oxidation states−3, −2, −1, 0, +1, +2, +3, +4, +5, +6, +7 (depending on the oxidation state, an acidic, basic, or amphoteric oxide)
ElectronegativityPauling scale: 1.55
Ionization energies
  • 1st: 717.3 kJ/mol
  • 2nd: 1509.0 kJ/mol
  • 3rd: 3248 kJ/mol
  • (more)
Atomic radiusempirical: 127 pm
Covalent radiusLow spin: 139±5 pm
High spin: 161±8 pm
Color lines in a spectral range
Spectral lines of manganese
Other properties
Natural occurrenceprimordial
Crystal structurebody-centered cubic (bcc)
Body-centered cubic crystal structure for manganese
Speed of sound 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 µΩ·m (at 20 °C)
Magnetic orderingparamagnetic
Magnetic susceptibility(α) +529.0·10−6 cm3/mol (293 K)[2]
Young's modulus198 GPa
Bulk modulus120 GPa
Mohs hardness6.0
Brinell hardness196 MPa
CAS Number7439-96-5
History
DiscoveryCarl Wilhelm Scheele (1774)
First isolationJohann Gottlieb Gahn (1774)
Main isotopes of manganese
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
52Mn syn 5.6 d ε 52Cr
β+ 52Cr
γ
53Mn trace 3.74×106 y ε 53Cr
54Mn syn 312.03 d ε 54Cr
γ
55Mn 100% stable
Category Category: Manganese
| references

Manganese is a chemical element with the symbol Mn and atomic number 25. It is not found as a free element in nature; it is often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels.

Historically, manganese is named for pyrolusite and other black minerals from the region of Magnesia in Greece, which also gave its name to magnesium and the iron ore magnetite. By the mid-18th century, Swedish-German chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine. Scheele and others were aware that pyrolusite (now known to be manganese dioxide) contained a new element, but they were unable to isolate it. Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, which he did by reducing the dioxide with carbon.

Manganese phosphating is used for rust and corrosion prevention on steel. Ionized manganese is used industrially as pigments of various colors, which depend on the oxidation state of the ions. The permanganates of alkali and alkaline earth metals are powerful oxidizers. Manganese dioxide is used as the cathode (electron acceptor) material in zinc-carbon and alkaline batteries.

In biology, manganese(II) ions function as cofactors for a large variety of enzymes with many functions.[3] Manganese enzymes are particularly essential in detoxification of superoxide free radicals in organisms that must deal with elemental oxygen. Manganese also functions in the oxygen-evolving complex of photosynthetic plants. While the element is a required trace mineral for all known living organisms, it also acts as a neurotoxin in larger amounts. Especially through inhalation, it can cause manganism, a condition in mammals leading to neurological damage that is sometimes irreversible.