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Potassium Dicyanoargentate
Potassium dicyanoargentate is an inorganic compound with the formula KAg(CN)2. A white solid, it is the K+ salt of the linear coordination complex g(CN)2sup>−. It forms upon treatment of virtually any silver salt with two equivalents of potassium cyanide. Uses and reactions KAg(CN)2 is significant adventitious product of gold mining using cyanide as an extractant. It can be used in silver plating, as a bactericide A bactericide or bacteriocide, sometimes abbreviated Bcidal, is a substance which kills bacteria. Bactericides are disinfectants, antiseptics, or antibiotics. However, material surfaces can also have bactericidal properties based solely on their p ..., and in the manufacture of antiseptics. It forms a variety of coordination polymers, a property that exploits the bridging tendency of the cyanide ligand. References Potassium compounds Silver compounds Cyano complexes {{inorganic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Dicyanoaurate
Potassium dicyanoaurate (or potassium gold cyanide) is an inorganic compound with formula . It is a colorless to white solid that is soluble in water and slightly soluble in alcohol. The salt itself is often not isolated, but solutions of the dicyanoaurate ion () are generated on a large scale in the extraction of gold from its ores. Production In mining of gold from dilute sources, gold is selectively extracted by dissolution in aqueous solutions of cyanide, provided by dissolving sodium cyanide, potassium cyanide and/or calcium cyanide. The reaction for the dissolution of gold, the "Elsner Equation", is: : In this process, oxygen is the oxidant. It can also be produced by reaction of gold(I) salts with excess potassium cyanide. : Structure : Potassium dicyanoaurate is a salt. The dicyanoaurate anion is linear according to X-ray crystallography. On the basis of infrared spectroscopy, the dicyanoaurate anion adopts a very similar structure in sodium dicyanoaurate (). Uses Di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep Mantle (geology), mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salt (chemistry), salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within life, living things. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Complex
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of chemical bond, bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing chemical compound, compounds, especially those that include transition metals (elements like titanium that belong to the periodic table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A Ligand#Polydentate and polyhapto ligand motifs and nomenclature, polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Cyanide
Potassium cyanide is a compound with the formula KCN. It is a colorless salt, similar in appearance to sugar, that is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications include jewellery for chemical gilding and buffing. Potassium cyanide is highly toxic, and a dose of 200 to 300 milligrams will kill nearly any human. The moist solid emits small amounts of hydrogen cyanide due to hydrolysis (reaction with water). Hydrogen cyanide is often described as having an odor resembling that of bitter almonds. The taste of potassium cyanide has been described as acrid and bitter, with a burning sensation similar to lye. Potassium cyanide kills so rapidly its taste hasn't been reliably documented, in 2006 an Indian man named M.P. Prasad committed suicide using potassium cyanide. He was a goldsmith and was aware of the mystery behind its taste. In the suicide note Prasad left, the final words written were that potassium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold Cyanidation
Gold cyanidation (also known as the cyanide process or the MacArthur–Forrest process) is a hydrometallurgical technique for extracting gold from low-grade ore through conversion to a water-soluble coordination complex. It is the most commonly used leaching process for gold extraction. Cyanidation is also widely used in silver extraction, usually after froth flotation. Production of reagents for mineral processing to recover gold represents 70% of cyanide consumption globally. While other metals, such as copper, zinc, and silver, are also recovered using cyanide, gold remains the primary driver of this technology. The highly toxic nature of cyanide has led to controversy regarding its use in gold mining, with it being banned in some parts of the world. However, when used with appropriate safety measures, cyanide can be safely employed in gold extraction processes. One critical factor in its safe use is maintaining an alkaline pH level above 10.5, which is typically controlle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Plating
Plating is a finishing process in which a metal is deposited on a surface. Plating has been done for hundreds of years; it is also critical for modern technology. Plating is used to decorate objects, for corrosion inhibition, to improve solderability, to harden, to improve wearability, to reduce friction, to improve paint adhesion, to alter conductivity, to improve IR reflectivity, for radiation shielding, and for other purposes. Jewelry typically uses plating to give a silver or gold finish. Thin-film deposition has plated objects as small as an atom, therefore plating finds uses in nanotechnology. There are several plating methods, and many variations. In one method, a solid surface is covered with a metal sheet, and then heat and pressure are applied to fuse them (a version of this is Sheffield plate). Other plating techniques include electroplating, vapor deposition under vacuum and sputter deposition. Recently, plating often refers to using liquids. Metallizing refers to co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bactericide
A bactericide or bacteriocide, sometimes abbreviated Bcidal, is a substance which kills bacteria. Bactericides are disinfectants, antiseptics, or antibiotics. However, material surfaces can also have bactericidal properties based solely on their physical surface structure, as for example biomaterials like insect wings. Disinfectants The most used disinfectants are those applying *active chlorine (i.e., hypochlorites, chloramines, dichloroisocyanurate and trichloroisocyanurate, wet chlorine, chlorine dioxide, etc.), *active oxygen (peroxides, such as peracetic acid, potassium persulfate, sodium perborate, sodium percarbonate, and urea perhydrate), *iodine (povidone-iodine, Lugol's solution, iodine tincture, iodinated nonionic surfactants), *concentrated alcohols (mainly ethanol, 1-propanol, called also n-propanol and 2-propanol, called isopropanol and mixtures thereof; further, 2-phenoxyethanol and 1- and 2-phenoxypropanols are used), *phenols, phenolic substances (such as ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA
The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with forecasting weather, monitoring oceanic and atmospheric conditions, charting the seas, conducting deep-sea exploration, and managing fishing and protection of marine mammals and endangered species in the US exclusive economic zone. The agency is part of the United States Department of Commerce and is headquartered in Silver Spring, Maryland. History NOAA traces its history back to multiple agencies, some of which are among the earliest in the federal government: * United States Coast and Geodetic Survey, formed in 1807 * Weather Bureau of the United States, formed in 1870 * Bureau of Commercial Fisheries, formed in 1871 (research fleet only) * Coast and Geodetic Survey Corps, formed in 1917 The most direct predecessor of NOAA was the Environmental Science Services Administration (ESSA), into which several existing scientific agencies such as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bridging Ligand
In coordination chemistry, a bridging ligand is a ligand that connects two or more atoms, usually metal ions. The ligand may be atomic or polyatomic. Virtually all complex organic compounds can serve as bridging ligands, so the term is usually restricted to small ligands such as pseudohalides or to ligands that are specifically designed to link two metals. In naming a complex wherein a single atom bridges two metals, the bridging ligand is preceded by the Greek letter mu, μ, with a subscript number denoting the number of metals bound to the bridging ligand. μ2 is often denoted simply as μ. When describing coordination complexes care should be taken not to confuse μ with η ('eta'), which relates to hapticity. Ligands that are not bridging are called terminal ligands. List of bridging ligands Virtually all ligands are known to bridge, with the exception of amines and ammonia. Common bridging ligands include most of the common anions. Many simple organic ligands form s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Compounds
Potassium is a chemical element; it has symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, which is easily removed to create an ion with a positive charge (which combines with anions to form salts). In nature, potassium occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in seawater (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, a common constituent of granites and oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Compounds
Silver is a relatively unreactive metal, although it can form several compounds. The common oxidation states of silver are (in order of commonness): +1 (the most stable state; for example, silver nitrate, AgNO3); +2 (highly oxidising; for example, silver(II) fluoride, AgF2); and even very rarely +3 (extreme oxidising; for example, potassium tetrafluoroargentate(III), KAgF4). The +3 state requires very strong oxidising agents to attain, such as fluorine or peroxodisulfate, and some silver(III) compounds react with atmospheric moisture and attack glass.Greenwood and Earnshaw, p. 1188 Indeed, silver(III) fluoride is usually obtained by reacting silver or silver monofluoride with the strongest known oxidizing agent, krypton difluoride.Greenwood and Earnshaw, p. 903 Oxides and chalcogenides Oxides Silver and gold have rather low chemical affinity, chemical affinities for oxygen, lower than copper, and it is therefore expected that silver oxides are thermally quite unstable. Soluble sil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
