|
Manganese Monophosphate
Manganese(III) phosphate is an inorganic chemical compound of manganese with the formula MnPO4. It is a hygroscopic purple solid that absorbs moisture to form the pale-green monohydrate, though the anhydrous and monohydrate forms are typically each synthesized by separate methods. Production and properties Manganese phosphate monohydrate is produced by the reaction of an Mn(II) salt, such as manganese(II) sulfate, and phosphoric acid, followed by oxidation by nitric acid. Another method of producing the monohydrate is by the comproportionation of permanganate and Mn(II) in phosphoric acid: :MnO4– + 4 Mn2+ + 10 PO43– + 8 H+ → 5 n(PO4)2sup>3– + 4 H2O The diphosphomanganate(III) ion slowly converts to the monohydrate. Heating of the monohydrate does not yield the anhydrous form, instead, it decomposes to manganese(II) pyrophosphate (Mn2P2O7) at 420 °C: :4 MnPO4·H2O → 2 Mn2P2O7 + 4 H2O + O2 To produce the anhydrous form, lithium manganese(II) phosphate is oxidized wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetonitrile
Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not classed as organic). It is produced mainly as a byproduct of acrylonitrile manufacture. It is used as a polar aprotic solvent in organic synthesis and in the purification of butadiene. The skeleton is linear with a short distance of 1.16 Å. Acetonitrile was first prepared in 1847 by the French chemist Jean-Baptiste Dumas. Applications Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower. Heat is then employed in the separatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithiophilite
Lithiophilite is a mineral containing the element lithium. It is lithium manganese(II) phosphate with chemical formula . It occurs in pegmatites often associated with triphylite, the iron end member in a solid solution series. The mineral with intermediate composition is known as sicklerite and has the chemical formula ). The name lithiophilite is derived from the Greek philos (φιλός) "friend," as lithiophilite is usually found with lithium. Lithiophylite is a resinous reddish to yellowish brown mineral crystallizing in the orthorhombic system often as slender prisms. It is usually associated with lepidolite, beryl, quartz, albite, amblygonite, and spodumene of pegmatitic origin. It rather readily weathers to a variety of secondary manganese phosphates and oxides. It is a late-stage mineral in some complex granite pegmatites. Members of the triphylite-lithiophilite series readily alter to secondary minerals. The type locality is the Branchville Quarry, Branchville, Fairfiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serrabrancaite
Serrabrancaite is a mineral with the chemical formula MnPO4•H2O and which is named for the locality where it was found, the Alto Serra Branca Pegmatite. The Alto Serra Branca mine has been in operation since the 1940s. It is located in Paraiba, Brazil near a village named Pedra Lavrada. Tantalite is the main mineral mined here. Specimens of serrabrancaite are kept in the Mineralogical Collections of both the Bergakademie Freiberg, Germany and the Martin-Luther Universität Halle, Institut für Geologische Wissenschaften. Occurrence The Alto Serra Branca Mine occurs where a granitic pegmatite intruded upon a biotite schist. There are many minerals found within this pegmatite. The main constituents are quartz, muscovite, microcline, and albite and amblygonite are common in smaller quantities. The minerals apatite, beryl, uraninite, and elbaite along with the tantalite group and other secondary uranium minerals are found throughout the mine. Near the center of the open portion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octahedral Molecular Geometry
In chemistry, octahedral molecular geometry, also called square bipyramidal, describes the shape of compounds with six atoms or groups of atoms or ligands symmetrically arranged around a central atom, defining the vertices of an octahedron. The octahedron has eight faces, hence the prefix ''octa''. The octahedron is one of the Platonic solids, although octahedral molecules typically have an atom in their centre and no bonds between the ligand atoms. A perfect octahedron belongs to the point group Oh. Examples of octahedral compounds are sulfur hexafluoride SF6 and molybdenum hexacarbonyl Mo(CO)6. The term "octahedral" is used somewhat loosely by chemists, focusing on the geometry of the bonds to the central atom and not considering differences among the ligands themselves. For example, , which is not octahedral in the mathematical sense due to the orientation of the bonds, is referred to as octahedral. The concept of octahedral coordination geometry was developed by Alfred ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kieserite
Kieserite, or magnesium sulfate monohydrate, is a hydrous magnesium sulfate mineral with formula (MgSO4·H2O). It has a vitreous luster and it is colorless, grayish-white or yellowish. Its hardness is 3.5 and crystallizes in the monoclinic crystal system. Gunningite is the zinc member of the kieserite group of minerals. Etymology It is named after Dietrich Georg von Kieser (Jena, Germany 1862) Occurrence Kieserite commonly occurs in marine evaporites and rarely in volcanic environments as a sublimate. It occurs in association with halite, carnallite, polyhalite, anhydrite, boracite, sulfoborite, leonite, epsomite and celestine. Mars In early 2005, Mars Express, a European Space Agency orbiter, discovered evidence of kieserite in patches of Valles Marineris (the largest canyon on Mars), along with gypsum and polyhydrated sulfates. This is direct evidence of Mars's watery past and augments similar discoveries made by the Mars Exploration Rover Opportunity in 2004. Moons o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic Crystal System
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal classes The table below organi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purpurite
Purpurite is a mineral, manganese phosphate, MnPO4 with varying amounts of iron depending upon its source. It occurs in color ranges from brownish black via purple and violet to dark red. Purpurite forms a series with the iron-bearing endmember heterosite, FePO4. See also *Manganese violet Manganese violet is the common name for ammonium manganese(III) pyrophosphate, an inorganic compound composed of ammonium (), manganese in the +3 oxidation state, and the pyrophosphate anion (). It is prepared by heating a mixture of manganese(II ... References Manganese(III) minerals Iron(III) minerals Phosphate minerals Orthorhombic minerals Minerals in space group 53 {{Phosphate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olivine
The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation. Olivine also has many other historical uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes. The ratio of magnesium to iron varies between the two endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as molar percentages of forsterite (Fo) and fayalite (Fa) (''e.g.'', Fo70Fa30). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purpurite - Sandamab Pegmatite, Erongo Region, Namibia 2
Purpurite is a mineral, manganese phosphate, MnPO4 with varying amounts of iron depending upon its source. It occurs in color ranges from brownish black via purple and violet to dark red. Purpurite forms a series with the iron-bearing endmember heterosite, FePO4. See also *Manganese violet Manganese violet is the common name for ammonium manganese(III) pyrophosphate, an inorganic compound composed of ammonium (), manganese in the +3 oxidation state, and the pyrophosphate anion (). It is prepared by heating a mixture of manganese(II ... References Manganese(III) minerals Iron(III) minerals Phosphate minerals Orthorhombic minerals Minerals in space group 53 {{Phosphate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitronium Tetrafluoroborate
Nitronium tetrafluoroborate is an inorganic compound with formula NO2BF4. It is a salt of nitronium cation and tetrafluoroborate anion. It is a colorless crystalline solid, which reacts with water to form the corrosive acids HF and HNO3. As such, it must be handled under water-free conditions. It is sparsely soluble in many organic solvents. Preparation Nitronium tetrafluoroborate can be prepared by adding a mixture of anhydrous hydrogen fluoride and boron trifluoride to a nitromethane solution of nitric acid or dinitrogen pentoxide. Applications Nitronium tetrafluoroborate is used as a nitration In organic chemistry, nitration is a general class of chemical processes for the introduction of a nitro group into an organic compound. The term also is applied incorrectly to the different process of forming nitrate esters between alcohols an ... agent. References Tetrafluoroborates Nitronium compounds {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese(II) Pyrophosphate
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 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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
