Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, 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. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as a rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide.

Manganese, ₂₅Mn

Pure manganese cube and oxidized manganese chips
Manganese
Pronunciation	/ˈmæŋɡəniːz/ ​(MANG-gə-neez)
Appearance	silvery metallic
Standard atomic weight Ar°(Mn)
	54.938043±0.000002 54.938±0.001 (abridged)
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 chromium ← manganese → iron
Atomic number (Z)	25
Group	group 7
Period	period 4
Block	d-block
Electron configuration	[Ar] 3d5 4s2
Electrons per shell	2, 8, 13, 2
Physical properties
Phase at STP	solid
Melting point	1519 K ​(1246 °C, ​2275 °F)
Boiling point	2334 K ​(2061 °C, ​3742 °F)
Density (near r.t.)	7.21 g/cm3
when liquid (at m.p.)	5.95 g/cm3
Heat of fusion	12.91 kJ/mol
Heat of vaporization	221 kJ/mol
Molar heat capacity	26.32 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)
Electronegativity	Pauling scale: 1.55
Ionization energies	1st: 717.3 kJ/mol 2nd: 1509.0 kJ/mol 3rd: 3248 kJ/mol (more)
Atomic radius	empirical: 127 pm
Covalent radius	Low spin: 139±5 pm High spin: 161±8 pm
Spectral lines of manganese
Other properties
Natural occurrence	primordial
Crystal structure	​body-centered cubic (bcc)
Speed of sound thin rod	5150 m/s (at 20 °C)
Thermal expansion	21.7 µm/(m⋅K) (at 25 °C)
Thermal conductivity	7.81 W/(m⋅K)
Electrical resistivity	1.44 µΩ⋅m (at 20 °C)
Magnetic ordering	paramagnetic
Molar magnetic susceptibility	(α) +529.0×10−6 cm3/mol (293 K)
Young's modulus	198 GPa
Bulk modulus	120 GPa
Mohs hardness	6.0
Brinell hardness	196 MPa
CAS Number	7439-96-5
History
Discovery	Carl Wilhelm Scheele (1774)
First isolation	Johann Gottlieb Gahn (1774)
Isotopes of manganese v e
Main isotopes Decay abun­dance half-life (t1/2) mode pro­duct 52Mn synth 5.591 d β+ 52Cr 53Mn trace 3.7×106 y ε 53Cr 54Mn synth 312.081 d ε 54Cr β− 54Fe β+ 54Cr 55Mn 100% stable
Category: Manganese view talk edit | references

Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes.

Manganese was first isolated in 1774. It is familiar in the laboratory in the form of the deep violet salt potassium permanganate. It occurs at the active sites in some enzymes. Of particular interest is the use of a Mn-O cluster, the oxygen-evolving complex, in the production of oxygen by plants.