Manganese

**Name:** Manganese
 * Symbol:** Mn
 * Atomic Number:** 25
 * Atomic Mass:** 54.93805 amu
 * Melting Point:** 1245.0 °C (1518.15 K, 2273.0 °F)
 * Boiling Point:** 1962.0 °C (2235.15 K, 3563.6 °F)
 * Number of Protons/Electrons:** 25
 * Number of Neutrons:** 30
 * Classification:** [|Transition Metal]

Group: 4**
 * Period: 7

**Number of Energy Levels:** 4
 * First Energy Level:** 2
 * Second Energy Level:** 8
 * Third Energy Level:** 13
 * Fourth Energy Level:** 2


 * Crystal Structure:** Cubic
 * Density @ 293 K:** 7.43 g/cm3
 * Color:** silverish/grayish


|| ** Half Life ** ||  ||  5.59 days ||  ||  21.1 minutes ||  ||  3700000.0 years ||  || <span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> 312.2 days ||  || <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Stable ||  || <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> 2.57 hours ||  || <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"> <span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;">1.45 minutes || <span style="color: #51a50d; font-family: Georgia, serif;">
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;">** Isotope **
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-52
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-52m
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-53
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-54
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-55
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-56
 * <span style="color: #db85fa; font-family: Impact, Charcoal, sans-serif;"><span style="color: #51a50d; font-family: Georgia, serif;"><span style="color: #a823e7; font-family: 'Comic Sans MS', cursive;"> Mn-57

<span style="color: #0af580; font-family: 'Comic Sans MS', cursive;"> **Date of Discovery:** 1774
 * Discoverer:** Johann Gahn
 * Name Origin:** From the Latin word //mangnes// (magnet)
 * Uses:** steel, batteries, ceramics
 * Obtained From:** pyrolusite, psilomelane, rhodochrosite

http://www.chemicalelements.com/elements/mn.html

=**//__History and Uses:__//**= Proposed to be an element by Carl Wilhelm Scheele in 1774, manganese was discovered by Johan Gottlieb Gahn, a Swedish chemist, by heating the mineral pyrolusite (MnO2) in the presence of charcoal later that year. Today, most manganese is still obtained from pyrolusite, although it is usually burned in a furnace with powdered [|aluminum] or is treated with sulfuric acid (H2SO4) to form manganese sulfate (MnSO4), which is then electrolyzed. Nearly 90% of all of the manganese produced each year is used in the production of steel. Manganese is added to molten steel to remove [|oxygen] and [|sulfur] and is alloyed with steel to make it easier to form and work with and to increase steel's strength and resistance to impact. Railroad tracks, for example, are made with steel that contains as much as 1.2% manganese. Manganese is also used to give glass an amethyst color and is responsible for the color of amethyst gemstones. Manganese dioxide (MnO2), the most common compound of manganese, makes up about 0.14% of [|the Earth's crust]. It is used in dry cell batteries to prevent the formation of [|hydrogen], to remove the green color in glass that is caused by the presence of [|iron] contaminants, and as a drying agent in black paints. Steel becomes harder when it is alloyed with manganese. It has similar applications when alloyed with aluminum and copper. Hardened steel is important in the manufacture of construction materials like I-beams (24% of manganese consumption), machinery (14% of manganese consumption), and transportation (13% of manganese consumption). Manganese dioxide is used to: manufacture ferroalloys; manufacture dry cell batteries (it's a depolarizer); to "decolorize" glass; to prepare some chemicals, like oxygen and chlorine; and to dry black paints. Manganese sulfate (MnSO4) is used as a chemical intermediate and as a micronutrient in animal feeds and plant fertilizers. Manganese metal is used as a brick and ceramic colorant, in copper and aluminum alloys, and as a chemical oxidizer and catalyst. Potassium permanganate (KMnO4) is used as a bactericide and algicide in water and wastewater treatment, and as an oxidant in organic chemical synthesis.

= **//__Isotopes__//** = Naturally occurring manganese is composed of 1 stable [|isotope]; 55Mn. 18 [|radioisotopes] have been characterized with the most stable being 53Mn with a [|half-life] of 3.7 million years, 54Mn with a half-life of 312.3 days, and 52Mn with a half-life of 5.591 days. All of the remaining [|radioactive] isotopes have half lives that are less than 3 hours and the majority of these have half lives that are less than 1 minute. This element also has 3 [|meta states]. Manganese is part of the [|iron] group of elements which are thought to be synthesized in large [|stars] shortly before [|supernova] explosion. 53Mn decays to 53[|Cr] with a [|half-life] of 3.7 million years. Because of its relatively short half-life, 53Mn is an extinct [|radionuclide]. Manganese isotopic contents are typically combined with [|chromium] isotopic contents and have found application in [|isotope geology] and [|radiometric dating]. Mn-Cr isotopic ratios reinforce the evidence from 26[|Al] and 107[|Pd] for the early history of the [|solar system]. Variations in 53Cr/52Cr and Mn/Cr ratios from several [|meteorites] indicate an initial 53Mn/55Mn ratio that suggests Mn-Cr isotopic systematics must result from in-situ decay of 53Mn in differentiated planetary bodies. Hence 53Mn provides additional evidence for [|nucleosynthetic] processes immediately before coalescence of the [|solar system]. The isotopes of manganese range in [|atomic weight] from 46 [|u] (46Mn) to 65 u (65Mn). The primary [|decay mode] before the most abundant stable isotope, 55Mn, is [|electron capture] and the primary mode after is [|beta decay]

= __//Biological role//__ = Manganese is an essential trace nutrient in all forms of life. The classes of enzymes that have manganese [|cofactors] are very broad and include such classes as [|oxidoreductases], [|transferases], [|hydrolases], [|lyases], [|isomerases], [|ligases], [|lectins], and [|integrins]. The [|reverse transcriptases] of many [|retroviruses] (though not [|lentiviruses] such as [|HIV]) contain manganese. The best known manganese-containing [|polypeptides] may be [|arginase], the [|diphtheria toxin], and Mn-containing [|superoxide dismutase] ([|Mn-SOD]). Mn-SOD is the type of SOD present in eukaryotic mitochondria, and also in most bacteria (this fact is in keeping with the bacterial-origin theory of mitochondria). The Mn-SOD enzyme is probably one of the most ancient, for nearly all organisms living in the presence of oxygen use it to deal with the toxic effects of [|superoxide], formed from the 1-electron reduction of dioxygen. Exceptions include a few kinds of bacteria such as [|Lactobacillus plantarum] and related [|lactobacilli], which use a different non-enzymatic mechanism, involving manganese (Mn2+) ions complexed with polyphosphate directly for this task, indicating how this function possibly evolved in aerobic life.The human body contains about 10 mg of manganese, which is stored mainly in the liver and kidneys. Manganese is also important in photosynthetic [|oxygen evolution] in [|chloroplasts] in plants. The [|oxygen evolving complex] (OEC), part of Photosystem II contained in the thylakoid membranes of chloroplasts, is responsible for the terminal [|photooxidation of water] during the [|light reactions] of [|photosynthesis], has a metalloenzyme core containing four atoms of manganese.[|[][|5][|]] For this reason, most broad-spectrum plant fertilizers contain manganese.

=//__Health Hazards and Risks__//= [|Hazards and risks] associated with manganese: manganese metal powder is a fire hazard. Unless known otherwise, all manganese compounds should be regarded as highly toxic as well as possibly carcinogenic and teratogenic. =//__Facts:__// =

=
Manganese is named from a corruption of the latin word for magnestism; magnes, in allusion to its prinicple ore's magnetic properties. However, manganese crystals have yet to be found in nature and therefore it is technically not a mineral, although laboratory grown specimens can look like a natural stone. The element manganese is an essential element in people's daily food consumption and has several industrial uses. Manganese is used in steel alloys to increase many favorable characteristics such as strength, hardness and durability. In fact steel can not be produced without manganese; it is an essential ingredient in the process. Manganese is also used to color glass an amethyst color. That is not so surprising since manganese is the trace element responsible for quartz's purple variety, amethyst. Manganese coloring ability in minerals is well known and appreciated. Manganese is chiefly responsible for the wonderful colors in rhodochrosite, purpurite, rhodonite, serandite and spessartine to name a few. Unfortunately most manganese oxide minerals tend to be black. Manganese is extracted from the ore minerals pyrolusite and rhodochrosite. Manganese nodules on the sea floor may one day provide an economic source as well.Manganese is gray-white metal with a pinkish tinge, and a very brittle but hard metallic element. Its atomic number 25. In 1774, while heating the mineral pyrolusite (MnO2, manganese dioxide) in a charcoal fire, the Swedish scientist Johann Gahn discovered manganese. The heat and carbon in the charcoal separated oxygen from the pyrolusite, leaving a metallic manganese residue. This chemical reaction is called a reduction reaction. Manganese is a reactive element that easily combines with ions in water and air. In the Earth, manganese is found in a number of minerals of different chemical and physical properties, but is never found as a free metal in nature. The most important mineral is pyrolusite, because it is the main ore mineral for manganese. Trace amounts of manganese are very important to good health. It makes bones strong yet flexible, and it aids the body in absorbing Vitamin B1. It also is an important activator for the body to use enzymes. As little as 0.00002% Mn in the human body is essential. Studies have shown that a lack of manganese leads to infertility in animals. ======

//__**Sources**__//
Over 80% of the known world manganese resources are found in South Africa and Ukraine. Other important manganese deposits are in China, Australia, Brazil, Gabon, India, and Mexico. The United States imports manganese ore because the manganese resources in the U.S. are relatively low in manganese content per ton of ore. Importing these ores is presently more economic than mining them locally.

Most manganese ore imported to the United States is used to manufacture intermediate manganese ferroalloy products and electrolytic manganese for use in dry-cell batteries. Only a small amount of the ore is directly used in the steel making process.

Some manganese is recovered through the reprocessing of scrap metals and steel slag, or the materials left over from the steel-making process. Though considered waste in terms of its steel content, slag often contains significant amounts of other elements that can be recovered.

Deep-sea nodules of manganese and other metals are scattered on the ocean floor. They form when the hot waters from hot springs (called black smokers) on the ocean bottom meet the cold, deep ocean water. The elements in the hot volcanic waters precipitate as nodules. Though rich in manganese (nearly 25% manganese) they are very deep in the ocean and it would cost too much to make them worth retrieving. This may prove to be an important source of manganese in the future should reserves in the Earth's crust be depleted and cost-effective deep-sea mining methods are discovered.

manganese flakes.. manganese mines....

=**//__The Isotopes of Manganese__//**=

Naturally occurring **[|manganese]** (**Mn**) is composed of 1 stable [|isotope]; 55Mn. 18 [|radioisotopes] have been characterized with the most stable being 53Mn with a [|half-life] of 3.7 million years, 54Mn with a half-life of 312.3 days, and 52Mn with a half-life of 5.591 days. All of the remaining [|radioactive] isotopes have half lives that are less than 3 hours and the majority of these have half lives that are less than 1 minute. This element also has 3 [|meta states]. Manganese is part of the [|iron] group of elements which are thought to be synthesized in large [|stars] shortly before [|supernova] explosion. 53Mn decays to 53[|Cr] with a [|half-life] of 3.7 million years. Because of its relatively short half-life, 53Mn is an extinct [|radionuclide]. Manganese isotopic contents are typically combined with [|chromium] isotopic contents and have found application in [|isotope geology] and [|radiometric dating]. Mn-Cr isotopic ratios reinforce the evidence from 26[|Al] and 107[|Pd] for the early history of the [|solar system]. Variations in 53Cr/52Cr and Mn/Cr ratios from several [|meteorites] indicate an initial 53Mn/55Mn ratio that suggests Mn-Cr isotopic systematics must result from in-situ decay of 53Mn in differentiated planetary bodies. Hence 53Mn provides additional evidence for [|nucleosynthetic] processes immediately before coalescence of the [|solar system]. The isotopes of manganese range in [|atomic weight] from 46 [|u] (46Mn) to 65 u (65Mn). The primary [|decay mode] before the most abundant stable isotope, 55Mn, is [|electron capture] and the primary mode after is [|beta decay]. Standard atomic mass: 54.938045(5) [|u]

=Cost of Manganese:= A metric ton unit that contains 50% **manganese** would have a value of $2 x 50 = **$100** per ton. At the price level of $2 per. 10 kilograms of **manganese.**
 * $100** per ton.


 * **__//Manganese//__** - The primary ores are oxides/hydroxides of manganese which include minerals such as hausmannite, pyrolusite, braunite, manganite, etc. and the carbonate, rhodochrosite. A large potential source is the deep sea manganese nodules.

||