"that take place in the substratum also affect the kinds of reductive processes that are found. The reactions that occur with permeable reactive barriers and ferrous iron are surface based. The surface reactions take three different forms: direct reduction, electron shunting through ferrous iron, and reduction by production and reaction of hydrogen. Pathway A represents direct electron transfer (ET) for Fe to the adsorbed halocarbon (RX) at the metal/water point of contact, resulting in dechlorination and production of Fe. Pathway B shows that Fe (resulting from corrosion of Fe) may also dechlorinate RX, producing Fe. Pathway C shows that H"
"FeS, Fe(CO), FeF, FeI, Fe(ONap), Fe(NO), Fe(CO), FeCO, FeO, FeO, FeO, Fe(CO), Fe(ClO), FePO, (NHSO)Fe, FeSO, Fe(SO), FeS Kr, KrF, add Krypton compounds here LaB, La(CO), LaCl, LaF, LaO, La(NO), LaPO, La(SO) Lr, add Lawrencium compounds here PbCO, PbCl, PbCl, PbO, PbF, PbI, Pb(CH), Pb(CH), Pb(NO), PbO, PbSO, PbS, PbSe, PbTe. LiH, LiN, LiNH, LiO, LiOH, LiF, LiCl, LiBr, LiI, LiCO, LiSO LuBr, Lu(CO), LuCl, LuF, LuI, Lu(NO), LuO, LuPO, Lu(SO), LuS Mg(HCO), MgB, MgBr, MgC, MgCO, MgCl, Magnesium citrate, MgNCN, MgF, MgPOF, Mg(HOCH(CHOH)CO), MgH, MgHPO, Mg(OH), Mg(OCl), MgI, MgMoO, Mg(NO), MgCO, MgO, MgO, Mg(PO), MgSiO, MgSO, MgS, MgTiO, MgWO,"
"window – not obstruct or detract from window detail. Iron - chemical symbol FE - the most commonly occurring (by weight) element on earth is, at the same time, the rarest in its elemental form. While the magma core of the earth is made mostly of iron and the red hills of the Rockies and brown and gold fieldstone all contain iron, the iron exists only in its various oxide forms. The only naturally occurring pure iron is found in fresh meteorites (and some very rare chemical situations - like bog iron in the New Jersey cedar swamps). Meteorites quickly"
"Germanium Germanium is a chemical element with symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Pure germanium is a semiconductor with an appearance similar to elemental silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom appears in high concentration, germanium was discovered comparatively late in the history of chemistry. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties"
"Ferricyanide Ferricyanide is the anion [Fe(CN)]. It is also called hexacyanoferrate(III) and in rare, but systematic nomenclature, hexacyanidoferrate(III). The most common salt of this anion is potassium ferricyanide, a red crystalline material that is used as an oxidant in organic chemistry. [Fe(CN)] consists of a Fe center bound in octahedral geometry to six cyanide ligands. The complex has O symmetry. The iron is low spin and easily reduced to the related ferrocyanide ion [Fe(CN)], which is a ferrous (Fe) derivative. This redox couple is reversible and entails no making or breaking of Fe-C bonds: This redox couple is a standard"
"Ammonium iron(III) sulfate Ammonium iron(III) sulfate, NHFe(SO)·12 HO, or NH[Fe(HO)](SO)·6 HO, also known as ferric ammonium sulfate (FAS) or iron alum, is a double salt in the class of alums, which consists of compounds with the general formula AB(SO) · 12 HO. It has the appearance of weakly violet, octahedrical crystals. There has been some discussion regarding the origin of the crystals' colour, with some ascribing it to impurities in the compound, and others claiming it to be a property of the crystal itself. FAS is paramagnetic, acidic and toxic towards microorganisms. It is a weak oxidizing agent, capable of"
"Iron(II,III) oxide Iron(II,III) oxide is the chemical compound with formula FeO. It occurs in nature as the mineral magnetite. It is one of a number of iron oxides, the others being iron(II) oxide (FeO), which is rare, and iron(III) oxide (FeO) also known as hematite. It contains both Fe and Fe ions and is sometimes formulated as FeO ∙ FeO. This iron oxide is encountered in the laboratory as a black powder. It exhibits permanent magnetism and is ferrimagnetic, but is sometimes incorrectly described as ferromagnetic. Its most extensive use is as a black pigment. For this purpose, it is"
"with acetic anhydride yields acetylferrocene just as acylation of benzene yields acetophenone under similar conditions. Iron-centered organometallic species are used as catalysts. The Knölker complex, for example, is a transfer hydrogenation catalyst for ketones. As iron has been in use for such a long time, it has many different names in different languages. The source of its chemical symbol ""Fe"" is the Latin word ""ferrum"", and its descendants are the names of the element in the Romance languages (for example, French ""fer"", Spanish ""hierro"", and Italian and Portuguese ""ferro""). The word ""ferrum"" itself possibly comes from the Semitic languages, via"
"Iron–nickel alloy An iron–nickel alloy or nickel–iron alloy, abbreviated FeNi or NiFe, is a group of alloys consisting primarily of the elements nickel (Ni) and iron (Fe). It is the main constituent of the ""iron"" planetary cores and iron meteorites. The acronym NiFe refers to various chemical reactions that involve an iron–nickel catalyst or component, or in geology, to the general composition of planetary cores (including Earth's). Some iron–nickel alloys are called nickel steel and usually contain additional elements, depending on the purpose. Iron and nickel are notable for being the final elements produced by stellar nucleosynthesis, and the heaviest"
"Potassium ferrate Potassium ferrate is the chemical compound with the formula KFeO. This purple salt is paramagnetic, and is a rare example of an iron(VI) compound. In most of its compounds, iron has the oxidation state +2 or +3 (Fe or Fe). Reflecting its high oxidation state, FeO is a powerful oxidizing agent. Georg Ernst Stahl (1660 – 1734) first discovered that the residue formed by igniting a mixture of potassium nitrate (saltpetre) and iron powder dissolved in water to give a purple solution. Edmond Frémy (1814 – 1894) later discovered that fusion of potassium hydroxide and iron(III) oxide in"
"on the half-life of 3.1×10 years has been established. Fe is an extinct radionuclide of long half-life (2.6 million years). It is not found on Earth, but its ultimate decay product is its granddaughter, the stable nuclide Ni. Much of the past work on isotopic composition of iron has focused on the nucleosynthesis of Fe through studies of meteorites and ore formation. In the last decade, advances in mass spectrometry have allowed the detection and quantification of minute, naturally occurring variations in the ratios of the stable isotopes of iron. Much of this work is driven by the Earth and"
"FeMoco FeMoco ( cofactor) is the primary cofactor of nitrogenase. Nitrogenase is the enzyme that catalyzes the conversion of atmospheric nitrogen molecules N into ammonia (NH) through the process known as nitrogen fixation. Containing iron and molybdenum, the cofactor is called FeMoco. Its stoichiometry is FeMoSC. The FeMo cofactor is a cluster with composition FeMoSC. Fe is the chemical symbol for the element iron (ferrum), and Mo is the symbol for molybdenum. This large cluster can be viewed as two subunits composed of one FeS (iron(III) sulfide) cluster and one MoFeS cluster. The two clusters are linked by three sulfide"
"performance of FeO using nanostructuring, surface functionalization, or by employing alternate crystal phases such as β-FeO. A mixture of zinc oxide with about 0.5% iron(III) oxide is called calamine, which is the active ingredient of calamine lotion. Iron(III) oxide Iron(III) oxide or ferric oxide is the inorganic compound with the formula FeO. It is one of the three main oxides of iron, the other two being iron(II) oxide (FeO), which is rare, and iron(II,III) oxide (FeO), which also occurs naturally as the mineral magnetite. As the mineral known as hematite, FeO is the main source of iron for the steel"
"Tris(acetylacetonato)iron(III) Tris(acetylacetonato) iron(III), often abbreviated Fe(acac), is a ferric coordination complex featuring acetylacetonate (acac) ligands, making it one of a family of metal acetylacetonates. It is a red air-stable solid that dissolves in nonpolar organic solvents. Fe(acac) is prepared by treating freshly precipitated Fe(OH) with acetylacetone. Fe(acac) is an octahedral complex with six equivalent Fe-O bonds with bond distances of about 2.00 Å. The regular geometry is consistent with a high-spin Fe core. As the metal orbitals are all evenly occupied the complex is not subject to Jahn-Teller distortions and thus adopts a D molecular symmetry. In contrast, the related"
"and health. Tellurium Tellurium is a chemical element with symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur. It is occasionally found in native form as elemental crystals. Tellurium is far more common in the universe as a whole than on Earth. Its extreme rarity in the Earth's crust, comparable to that of platinum, is due partly to its high atomic number, but also to its formation of a volatile hydride which caused it to be lost to space as a gas during the hot nebular"
"Iron(II,III) sulfide Iron(II,III) sulfide is a blue-black (sometimes pinkish) chemical compound of iron and sulfur with formula FeS or FeS·FeS, which is much similar to iron(II,III) oxide. It occurs naturally as the sulfide mineral greigite and is magnetic. It is a bio-mineral produced by and found in magnetotactic bacteria. It is a mixed valence compound, featuring both Fe and Fe centers, in 1:2 ratio. The crystallographic unit cell is cubic, with space group Fd3m. The S anions form a cubic close-packed lattice, and the Fe cations occupy both tetrahedral and octahedral sites. Like the related oxide magnetite (FeO), iron(II,III) sulfide"
"In the cluster FeBr the cation Fe stands for [FeO(OH)(tacn)], with tacn representing 1,4,7-triazacyclononane. The ferrous cube complex FeCHNO (commonly called [Fe(sae)(MeOH)]) was the first example of a single-molecule magnet involving an Fe(II) cluster, and the core of this complex is a slightly distorted cube with Fe and O atoms on alternating corners. Remarkably, this single-molecule magnet exhibits non-collinear magnetism, in which the atomic spin moments of the four Fe atoms point in opposite directions along two nearly perpendicular axes. Theoretical computations showed that approximately two magnetic electrons are localized on each Fe atom, with the other atoms being nearly"
"Symbol (chemistry) In relation to the chemical elements, a symbol is a code for a chemical element. Many functional groups have their own chemical symbol, e.g. Ph for the phenyl group, and Me for the methyl group. Chemical symbols for elements normally consist of one or two letters from the Latin alphabet, but can contain three when the element has a systematic temporary name (as of March 2017, no discovered elements have such a name), and are written with the first letter capitalized. Earlier chemical element symbols stem from classical Latin and Greek vocabulary. For some elements, this is because"
"Ferrous In chemistry, ferrous (Fe), indicates a divalent iron compound (+2 oxidation state), as opposed to ferric, which indicates a trivalent iron compound (+3 oxidation state). This usage has decreased, with current IUPAC nomenclature having names containing the oxidation state in bracketed Roman numerals instead, such as iron(II) oxide for ferrous oxide (FeO), and iron(III) oxide for ferric oxide (FeO). Outside chemistry, ""ferrous"" indicates the presence of iron. The word is derived from the Latin word """" (""iron""). Ferrous metals include steel and pig iron (with a carbon content of a few percent) and alloys of iron with other metals"
"in electrochemistry. Compared to normal cyanides like potassium cyanide, ferricyanides are much less toxic because of the tight hold of the CN to the Fe. They do react with mineral acids, however, to release highly toxic hydrogen cyanide gas. Treatment of ferricyanide with ferrous (Iron (II)) salts affords the brilliant, long-lasting pigment Prussian blue, the traditional color of blueprints. Ferricyanide Ferricyanide is the anion [Fe(CN)]. It is also called hexacyanoferrate(III) and in rare, but systematic nomenclature, hexacyanidoferrate(III). The most common salt of this anion is potassium ferricyanide, a red crystalline material that is used as an oxidant in organic chemistry."
"Iron(III) nitrate Iron(III) nitrate, or ferric nitrate, is the chemical compound with the formula Fe(NO). Since it is deliquescent, it is commonly found in its nonahydrate form Fe(NO)·9HO in which it forms colourless to pale violet crystals. When dissolved, it forms yellow solution due to hydrolysis. The compound is prepared by treating iron metal powder with nitric acid. Ferric nitrate is the catalyst of choice for the synthesis of sodium amide from a solution of sodium in ammonia: Certain clays impregnated with ferric nitrate have been shown to be useful oxidants in organic synthesis. For example, ferric nitrate on Montmorillonite—a"
"Barium ferrite Barium ferrite, abbreviated BaFe, BaM, is the chemical compound with the formula BaFeO. This and related ferrite materials are components in magnetic stripe cards and loudspeaker magnets. BaFe is described as Ba(Fe)(O). The Fe centers are ferromagnetically coupled. This area of technology is usually considered to be an application of the related fields of materials science and solid state chemistry. Barium ferrite is a highly magnetic material, has a high packing density, and is a metal oxide. Studies of this material date at least as far back as 1931, and it has found applications in magnetic card strips,"
"Panethite Panethite (Na,Ca)(Mg,Fe)(PO) is a rare phosphate mineral that was only found in one meteorite on Earth. It was originally found in the Dayton meteorite in Ohio. It is classified as H-M symbol (2/m) with space group of ""P""2/n. It is amber in color. It was named in the honor of Friedrich Adolf Paneth (1887–1958), a German chemist who made many contributions toward the discovery of the origin of the universe, and especially studies of meteorites. Using X-ray diffraction, the unit cell and the space group parameters were determined. The strongest lines of the X-ray were 5.10(6), 3.236(5), 3.007(10), 2.749,"
"how nucleosynthesis works, Fe is a more common endpoint of fusion chains inside extremely massive stars and is therefore more common in the universe, relative to other metals, including Ni, Fe and Ni, all of which have a very high binding energy. The isotope Fe is widely used in Mössbauer spectroscopy and the related nuclear resonance vibrational spectroscopy due to the low natural variation in energy of the 14.4 keV nuclear transition. The transition was famously used to make the first definitive measurement of gravitational redshift, in the 1960 Pound-Rebka experiment. Iron-60 is an iron isotope with a half-life of"
"Hafnium Hafnium is a chemical element with symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1923, by Coster and Hevesy, making it the last stable element to be discovered. Hafnium is named after ""Hafnia"", the Latin name for Copenhagen, where it was discovered. Hafnium is used in filaments and electrodes. Some semiconductor fabrication processes use its oxide for integrated circuits at 45 nm and smaller feature lengths. Some superalloys"
"Iron(III) oxide Iron(III) oxide or ferric oxide is the inorganic compound with the formula FeO. It is one of the three main oxides of iron, the other two being iron(II) oxide (FeO), which is rare, and iron(II,III) oxide (FeO), which also occurs naturally as the mineral magnetite. As the mineral known as hematite, FeO is the main source of iron for the steel industry. FeO is readily attacked by acids. Iron(III) oxide is often called rust, and to some extent this label is useful, because rust shares several properties and has a similar composition. To a chemist, rust is considered"
"of HAsSH. Analysis of classical oxidation states would recommend the description of arsenopyrite as Fe[AsS]. Iron-pyrite FeS represents the prototype compound of the crystallographic pyrite structure. The structure is simple cubic and was among the first crystal structures solved by X-ray diffraction. It belongs to the crystallographic space group ""Pa"" and is denoted by the Strukturbericht notation C2. Under thermodynamic standard conditions the lattice constant formula_1 of stoichiometric iron pyrite FeS amounts to . The unit cell is composed of a Fe face-centered cubic sublattice into which the S ions are embedded. The pyrite structure is also used by other"
"level and reversed both the metal-induced stabilization of HIF-1- and HIF-1α-dependent gene expression. Nickel Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. Pure nickel, powdered to maximize the reactive surface area, shows a significant chemical activity, but larger pieces are slow to react with air under standard conditions because an oxide layer forms on the surface and prevents further corrosion (passivation). Even so, pure native nickel is found in Earth's crust only in tiny"
"Fermium Fermium is a synthetic element with symbol Fm and atomic number 100. It is an actinide and the heaviest element that can be formed by neutron bombardment of lighter elements, and hence the last element that can be prepared in macroscopic quantities, although pure fermium metal has not yet been prepared. A total of 19 isotopes are known, with Fm being the longest-lived with a half-life of 100.5 days. It was discovered in the debris of the first hydrogen bomb explosion in 1952, and named after Enrico Fermi, one of the pioneers of nuclear physics. Its chemistry is typical"
"Tellurium Tellurium is a chemical element with symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur. It is occasionally found in native form as elemental crystals. Tellurium is far more common in the universe as a whole than on Earth. Its extreme rarity in the Earth's crust, comparable to that of platinum, is due partly to its high atomic number, but also to its formation of a volatile hydride which caused it to be lost to space as a gas during the hot nebular formation of"
"Paneth (1887-1958). Panethite Panethite (Na,Ca)(Mg,Fe)(PO) is a rare phosphate mineral that was only found in one meteorite on Earth. It was originally found in the Dayton meteorite in Ohio. It is classified as H-M symbol (2/m) with space group of ""P""2/n. It is amber in color. It was named in the honor of Friedrich Adolf Paneth (1887–1958), a German chemist who made many contributions toward the discovery of the origin of the universe, and especially studies of meteorites. Using X-ray diffraction, the unit cell and the space group parameters were determined. The strongest lines of the X-ray were 5.10(6), 3.236(5),"
"detection and quantification of minute, naturally occurring variations in the ratios of the stable isotopes of iron. Much of this work has been driven by the Earth and planetary science communities, although applications to biological and industrial systems are beginning to emerge. Fe is observationally stable, but theoretically can decay to Cr, with a half-life of more than 3.1x10 years via double electron capture (εε). The isotope Fe is the isotope with the lowest mass per nucleon, 930.412 MeV/c, though not the isotope with the highest nuclear binding energy per nucleon, which is nickel-62. However, because of the details of"
"Francium Francium is a chemical element with symbol Fr and atomic number 87. It used to be known as eka-caesium. It is extremely radioactive; its most stable isotope, francium-223 (originally called actinium K after the natural decay chain it appears in), has a half-life of only 22 minutes. It is the second-least electronegative element, behind only caesium, and is the second rarest naturally occurring element (after astatine). The isotopes of francium decay quickly into astatine, radium, and radon. As an alkali metal, it has one valence electron. Bulk francium has never been viewed. Because of the general appearance of the"