Manganese

Manganese (<img src="/1b37e673-feb2-5c28-bd2d-3a88d68b8826.png"/> <a href="http://en.wikipedia.org/wiki/Wikipedia:IPA_for_English" title="Wikipedia:IPA for English" >/</a><a href="http://en.wikipedia.org/wiki/Wikipedia:IPA_for_English#Key" title="Wikipedia:IPA for English" >ˈmæŋɡəniːz</a><a href="http://en.wikipedia.org/wiki/Wikipedia:IPA_for_English" title="Wikipedia:IPA for English" >/</a> <a href="http://en.wikipedia.org/wiki/Wikipedia:Pronunciation_respelling_key" title="Wikipedia:Pronunciation respelling key" >mang-gə-neez</a>) is a <a href="http://en.wikipedia.org/wiki/Chemical_element" title="Chemical element" >chemical element</a>, designated by the symbol Mn. It has the <a href="http://en.wikipedia.org/wiki/Atomic_number" title="Atomic number" >atomic number</a> 25. It is found as a <a href="http://en.wikipedia.org/wiki/Oxidation_state" title="Oxidation state" >free element</a> in nature (often in combination with iron), and in many minerals. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels.

Historically, manganese is named for various black minerals (such as <a href="http://en.wikipedia.org/wiki/Pyrolusite" title="Pyrolusite" >pyrolusite</a>) from the same region of <a href="http://en.wikipedia.org/wiki/Magnesia_(regional_unit)" title="Magnesia (regional unit)" >Magnesia</a> in Greece which gave names to similar-sounding<a href="http://en.wikipedia.org/wiki/Magnesium" title="Magnesium" >magnesium</a>, Mg, and <a href="http://en.wikipedia.org/wiki/Magnetite" title="Magnetite" >magnetite</a>, an ore of the element iron, Fe. By the mid-18th century, Swedish chemist <a href="http://en.wikipedia.org/wiki/Carl_Wilhelm_Scheele" title="Carl Wilhelm Scheele" >Carl Wilhelm Scheele</a> had used pyrolusite to produce<a href="http://en.wikipedia.org/wiki/Chlorine" title="Chlorine" >chlorine</a>. Scheele and others were aware that pyrolusite (now known to be manganese dioxide) contained a new element, but they were not able to isolate it. <a href="http://en.wikipedia.org/wiki/Johan_Gottlieb_Gahn" title="Johan Gottlieb Gahn" >Johan Gottlieb Gahn</a> was the first to isolate an impure sample of manganese metal in 1774, by <a href="http://en.wikipedia.org/wiki/Reduction-oxidation" title="Reduction-oxidation" class="mw-redirect" >reducing</a> the dioxide with <a href="http://en.wikipedia.org/wiki/Carbon" title="Carbon" >carbon</a>.

<a href="http://en.wikipedia.org/wiki/Phosphate_conversion_coating" title="Phosphate conversion coating" >Manganese phosphating</a> is used as a treatment for rust and corrosion prevention on steel. Depending on their oxidation state, manganese ions have various colors and are used industrially as <a href="http://en.wikipedia.org/wiki/Pigment" title="Pigment" >pigments</a>. The <a href="http://en.wikipedia.org/wiki/Permanganate" title="Permanganate" >permanganates</a> of <a href="http://en.wikipedia.org/wiki/Alkali_metal" title="Alkali metal" >alkali</a> and <a href="http://en.wikipedia.org/wiki/Alkaline_earth_metals" title="Alkaline earth metals" class="mw-redirect" >alkaline earth metals</a> are powerful oxidizers. Manganese dioxide is used as the cathode (electron acceptor) material in standard and alkaline disposable <a href="http://en.wikipedia.org/wiki/Dry_cell" title="Dry cell" class="mw-redirect" >dry cells</a> and batteries.

In biology, manganese(II) ions function as <a href="http://en.wikipedia.org/wiki/Cofactor_(biochemistry)" title="Cofactor (biochemistry)" >cofactors</a> for a large variety of enzymes with many functions. Manganese enzymes are particularly essential in detoxification of<a href="http://en.wikipedia.org/wiki/Superoxide" title="Superoxide" >superoxide</a> free radicals in organisms that must deal with elemental oxygen. Manganese also functions in the oxygen-evolving complex of photosynthetic plants. The element is a required trace mineral for all known living organisms. In larger amounts, and apparently with far greater activity by inhalation, manganese can cause a<a href="http://en.wikipedia.org/wiki/Manganism" title="Manganism" >poisoning syndrome</a> in mammals, with neurological damage which is sometimes irreversible.

Manganese

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