Initially, copper is oxidized to the cuprous ion: (1) Cu → Cu+ \+ e− The cuprous ion reacts with the chloride ion to form the insoluble white colored salt cuprous chloride: (2) Cu+ \+ Cl− → CuCl The cuprous chloride reacts with atmospheric moisture and oxygen to form a green cupric chloride/cupric hydroxide compound and hydrochloric acid: (3) 4 CuCl + 4 H2O + O2 → CuCl2·3 Cu(OH)2 \+ 2 HCl The remaining copper is oxidised by air to the cuprous ion: (4) Cu → Cu+ \+ e− The cuprous ion reacts with the chloride ion in the hydrochloric acid to form the insoluble white colored salt cuprous chloride: (5) Cu+ \+ Cl− → CuCl The reaction then repeats from equation (3). It is the presence of two different white and green salts that lead to the fuzzy green appearance.
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The arylation of alkylthiolates proceeds by the intermediacy of cuprous thiolates.
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This is olive brown in colour. When heated to 250 °C it recrystallizes to another yellow form. Cuprous sufoxylate Cu2SO2 can be made as a solid or liquid by heating cuprous sulfide and copper sulfate. Cu2SO2 melts at and is stable as a liquid phase to over 680K.
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The kinetics of absorption of oxygen in aqueous solutions of acidic chromous chloride and ammoniacal cuprous chloride were studied in a stirred cell.
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To maintain and increase output levels, Norilsk Nickel was planning to switch to mining a greater proportion of cuprous and disseminated ores rather than nickel-rich ores, which were being depleted. Norilsk Nickel also was developing new mines to replace depleted reserves of nickel-rich ore. The company's cuprous ore reserves, which are abundant, have a much lower nickel content and a somewhat lower copper content, and the disseminated ores are lower in all base-metals content than the nickel-rich ores. The nickel-rich, cuprous, and disseminated ores, however, are not greatly dissimilar in their PGM content.
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The pits that penetrate the bore are usually covered in a hard pale green nodule of copper sulfate and copper hydroxide salts. If the nodule is removed a hemispherical pit is revealed filled with coarse crystals of red cuprous oxide and green cuprous chloride. The pits are often referred to as Type 1 pits and the form of attack as Type 1 pitting.
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It forms a characteristic explosive solid upon treatment to its aqueous solution with ammoniacal silver nitrate. An amorphous explosive precipitate forms with ammoniacal cuprous chloride.
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One chemical treatment is soaking the object in a 5% sodium sesquicarbonate solution. This serves to neutralize the acid that attacks the metal as well as converting the reactive cuprous chloride to largely inert cuprous oxide. The oxide may coat the artefact with unsightly but harmless black spots or generally, darken the metal. The duration of soaking may be days to weeks or even a year for severely contaminated objects.
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This is accomplished by the Gattermann-Koch reaction, accomplished by treating benzene with carbon monoxide and hydrogen chloride under high pressure, catalyzed by a mixture of aluminium chloride and cuprous chloride.
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Copper(I) thiocyanate (or cuprous thiocyanate) is a coordination polymer with formula CuSCN. It is an air-stable, white solid used as a precursor for the preparation of other thiocyanate salts.
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This kind of corrosion is known as red plague. Little evidence exists for cuprous hydroxide, which is expected to rapidly undergo dehydration. A similar situation applies to the hydroxides of gold(I) and silver(I).
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Copper(I) nitrate (cuprous nitrate) with a molecular formula of CuNO3 is a compound with copper in a +1 oxidation state. Complexes containing copper(I) nitrate are numerous and include those with triphenylphosphine triphenylarsine and triphenylstibine.
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For example, cuprous cyanide gives the corresponding nitriles: :AN2+ + Y^- -> AY + N2 Aryldiazonium couple with electron-rich aromatic compounds such as a phenol to form azo compounds. Such reactions are widely applied to the production of dyes.
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Low Density Copper - replaces the core of traditional Cuprous Oxide with environmentally friendly materials found naturally in the ocean. The result is a copper biocide that provides the performance of a conventional cuprous oxide antifoulant while reducing the amount of copper introduced into the environment. Irgarol - is used in many dual biocide products, Irgarol is an algicide designed for use in antifouling paints to prevent soft growth such as algae and grasses. Water Based (Hydrocoat Technology)- This formula uses water to replace the harsh solvents found in conventional antifouling paints.
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A sample of copper(I) oxide. Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. Copper compounds, whether organic complexes or organometallics, promote or catalyse numerous chemical and biological processes.
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Aqueous cuprous chloride solutions react with base to give the same material. In all cases, the color is highly sensitive to the procedural details. Pourbaix diagram for copper in uncomplexed media (anions other than OH− not considered). Ion concentration 0.001 m (mol/kg water).
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The Rosenmund–von Braun synthesis is an organic reaction in which an aryl halide reacts with cuprous cyanide to yield an aryl nitrile. :Rosenmund–von Braun synthesis The reaction was named after Karl Wilhelm Rosenmund who together with his Ph.D. student Erich Struck discovered in 1914 that aryl halide reacts with alcohol water solution of potassium cyanide and catalytic amounts of cuprous cyanide at 200 °C. The reaction yields the carboxylic acid, not the nitrile, but Rosenmund speculated that the intermediate should be the nitrile. Independently Alfred Pongratz and Julius von Braun improved the reaction by changing the reaction conditions to higher temperatures and used no solvent for the reaction.
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The cyano group usually cannot be introduced by nucleophilic substitution of haloarenes, but such compounds can be easily prepared from diazonium salts. Illustrative is the preparation of benzonitrile using the reagent cuprous cyanide: :C6H5N+2 + CuCN -> C6H5CN + Cu+ + N2 This reaction is a special type of Sandmeyer reaction.
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As with other elements, the simplest compounds of copper are binary compounds, i.e. those containing only two elements, the principal examples being oxides, sulfides, and halides. Both cuprous and cupric oxides are known. Among the numerous copper sulfides, important examples include copper(I) sulfide and copper(II) sulfide.
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Sodium sesquicarbonate is used in bath salts, swimming pools, as an alkalinity source for water treatment, and as a phosphate-free product replacing the trisodium phosphate for heavy duty cleaning. Sodium sesquicarbonate is used in the conservation of copper and copper alloy artifacts that corrode due to contact with salt (called "bronze disease" due to its effect on bronze). The chloride from salt forms copper(I) chloride. In the presence of oxygen and water, even the small amount of moisture in the atmosphere, the cuprous chloride forms copper(II) chloride and hydrochloric acid, the latter of which dissolves the metal and forms more cuprous chloride in a self-sustaining reaction that leads to the entire destruction of the object.
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The compound crystallizes in the motif seen for cuprous oxide: gold is 2-coordinate, sulfur 4-coordinate, and the S-Au-S linkage is linear.Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. . Linear coordination geometry is typical of gold(I) compounds, e.g. the coordination complex chloro(dimethyl sulfide)gold(I).
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Copper(I) acetylide, or cuprous acetylide, is a chemical compound with the formula Cu2C2. Although never characterized by X-ray crystallography, the material has been claimed at least since 1856. One form is claimed to be a monohydrate with formula .). It is a reddish solid, that easily explodes when dry.
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Cuprous oxide is commonly used as a pigment, a fungicide, and an antifouling agent for marine paints. Rectifier diodes based on this material have been used industrially as early as 1924, long before silicon became the standard. Copper(I) oxide is also responsible for the pink color in a positive Benedict's test.
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When Collins removed the mass from the test tube, it bounced. Further analysis showed that the mass was a polymer of chloroprene, formed with chlorine from the cuprous chloride catalyst. Collins had stumbled upon a new synthetic rubber. Following this breakthrough, DuPont began to manufacture its first artificial rubber, DuPrene, in September 1931.
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The Glaser coupling is a type of coupling reaction. It is by far the oldest acetylenic coupling and is based on cuprous salts like copper(I) chloride or copper(I) bromide and an additional oxidant like oxygen. The base in its original scope is ammonia. The solvent is water or an alcohol.
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Copper(I) fluoride or cuprous fluoride is an inorganic compound with the chemical formula CuF. Its existence is uncertain. It was reported in 1933 to have a sphalerite-type crystal structure. Modern textbooks state that CuF is not known, since fluorine is so electronegative that it will always oxidise copper to its +2 oxidation state.
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The Leuckart thiophenol reaction is the decomposition of a diazoxanthate, by gentle warming in a slightly acidic cuprous medium, to its corresponding aryl xanthates which give aryl thiols on alkaline hydrolysis and aryl thioethers on further warming. Reaction pathway and mechanism This reaction was first reported by Rudolf Leuckart in 1890.Merck Index 14th Ed.
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This behavior was fully reversible and excluded non- equilibrium effects. Tubandt and Lorenz described other materials with a similar behavior, such as α-CuI, α-CuBr, β-CuBr, and high-temperature phases of Ag2S, Ag2Se and Ag2Te. They associated the conductivity with cations in silver and cuprous halides and with ions and electrons in silver chalcogenides.
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Copper(I) oxide or cuprous oxide is the inorganic compound with the formula Cu2O. It is one of the principal oxides of copper, the other being CuO or cupric oxide. This red-coloured solid is a component of some antifouling paints. The compound can appear either yellow or red, depending on the size of the particles.
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The trough and ore is highly deformed and suffers significant post- deposition dislocation by a series of north-south trending strike-slip faults. The komatiite locally is highly magnesian and favours talc-magnesite assemblages, having been intensely talc-carbonated. Accessory minerals observed in the ore body include nickeline, nickeliferous chalcopyrite, cuprous pentlandite, arsenian pentlandite, violarite and arsenopyrite.
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Bronze disease is the chloride corrosion of cuprous (copper-based) artefacts. It was originally thought to be caused by bacteria. It is contagious in that the chlorides which cause it can spread the condition if they are brought into contact with another cupreous object. Despite its name, bronze disease can affect any copper-bearing alloy, not just bronze.
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The compound is prepared by oxidizing the mixture of potassium chloride and cuprous chloride with fluorine: :3 KCl + CuCl + 3 F2 → K3CuF6 \+ 2 Cl2 A variety of analogues are known.R. Hoppe, G. Wingefeld "Zur Kenntnis der Hexafluorocuprate(III)" Zeitschrift für anorganische und allgemeine Chemie 1984, Vol. 519, pages 195–203. The compound reacts with water easily, producing oxygen and copper(II) products.
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After the formation of a pale-yellow solution, which indicates the completion of the diazotization reaction, the pH should be adjusted to 6. After this, the solution is introduced to a mixture of cuprous cyanide and toluene. At room temperature the toluene layer is removed. The aqueous layer is washed and dried and the purified product is isolated by crystallization.
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Eraclius’ De Coloribus et Artibus includes instructions for creating green and red glass by adding copper (probably in the form of ore or copper filings) to the batch, a method practiced since ancient times. (The chapters on how to make red, green and blue glass are missing from De Divers Artibus.) As with the iron/manganese colours, the colours formed by the addition of copper oxide to the glass are dependent on the different oxidation states of the added copper. In an oxidising environment blue cupric (Cu2+) ions are formed, in a strongly reducing environment red colloidal cuprous (Cu1+) oxide is formed and if reoxidised then green cuprous (Cu1+) oxide results. The production of bright reds and blues in particular was straightforward, as the addition of copper to the mix resulted in the reliable creation of red, blue and green.
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Copper(II) oxide or cupric oxide is the inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper, the other being Cu2O or copper(I) oxide (cuprous oxide). As a mineral, it is known as tenorite. It is a product of copper mining and the precursor to many other copper-containing products and chemical compounds.
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He found that when cuprous chloride and magnesium were used in either plain water or salt water, an improved battery resulted. Less than a month after filing, Adams brought his discovery to the attention of the Army and Navy. Arrangements were made for demonstrations before experts of the United States Army Signal Corps. The Signal Corps scientists did not believe the battery was workable.
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The name Cyprus is a derivative of Kúpros, which the Greeks called the island, and means Cuprous, synonymous with copper. Copper production can be dated to the fourth millennium BC, when it was used to make tools. The people of ancient Cyprus were known for their metalworking skills. To extract the high grade metal copper, called "copper talents", they prospected most of the areas containing copper.
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This method utilized a pill containing compounds that dissolved with a strong exothermic reaction without the use of an external heat source. The pill consisted primarily of citric acid monohydrate, sodium hydroxide, and copper sulfate, and a color change (cuprous oxide) was used to identify glucose. Some of Dr. Kamlet’s other inventions dealt with animal feed. One such invention used newsprint for cattle feed.
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Copper(I) iodide is the inorganic compound with the formula CuI. It is also known as cuprous iodide. It is useful in a variety of applications ranging from organic synthesis to cloud seeding. Pure copper(I) iodide is white, but samples are often tan or even, when found in nature as rare mineral marshite, reddish brown, but such color is due to the presence of impurities.
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Dates, especially cultivars like Shahani, Rotab, Qasb and Kharak; and also citruses like lemon, orange, tangerine, citrus limetta, bitter orange, and citron are the most well-known products of Jahrom. orange blossom, lemon juice, and date-based sweets like Ranginak and different halvas are also produced in Jahrom. Giveh, carpet, felt, kilim, cuprous dishes, and wickers are handicrafts of the city. Jahromi Gheimeh is a special Gheimeh cooked in Jahrom.
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Copper phosphide, 3, also copper(I) phosphide, cuprous phosphide, cuprophosphorus and phosphor copper, is a compound of copper and phosphorus, a phosphide of copper. It has the appearance of yellowish-grey very brittle mass of crystalline structure. It does not react with water. Recent crystallographic investigations have proven Cu3P to be copper deficient, which means that the sum formula of this compound is more accurately expressed as Cu3−xP.
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Some applications use shellac mixed with other natural or synthetic resins, such as pine resin or phenol- formaldehyde resin, of which Bakelite is the best known, for electrical use. Mixed with other resins, barium sulfate, calcium carbonate, zinc sulfide, aluminium oxide and/or cuprous carbonate (malachite), shellac forms a component of heat-cured capping cement used to fasten the caps or bases to the bulbs of electric lamps.
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While the reaction can be performed using commercial sources of copper(I) such as cuprous bromide or iodide, the reaction works much better using a mixture of copper(II) (e.g. copper(II) sulfate) and a reducing agent (e.g. sodium ascorbate) to produce Cu(I) in situ. As Cu(I) is unstable in aqueous solvents, stabilizing ligands are effective for improving the reaction outcome, especially if tris-(benzyltriazolylmethyl)amine (TBTA) is used.
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These polymers are made through oxidative coupling of substituted phenol in the presence of oxygen and copper and amine containing catalysts, such as cuprous bromide and pyridine. See Figure 2 for the PPO structure. PPO polymers can be classified as plastic resins. They and their composites with polystyrene, glass, and nylon are used as high-strength, moisture-resistant engineering plastics in a number of industries, including computer, telecommunication, and automotive parts.
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Red plague is an accelerated corrosion of copper when plated with silver. After storage or use in high-humidity environment, cuprous oxide forms on the surface of the parts. The corrosion is identifiable by presence of patches of brown-red powder deposit on the exposed copper. Red plague is caused by normally occurring electrode potential difference between the copper and silver, leading to galvanic corrosion occurring in pits or breaks in the silver plating.
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Copper Free - Econea is a non-metal biocide which is extremely effective against hard-shelled fouling organisms including barnacles, hydroids, mussels, oysters and tube worms. Econea should always be combined with a secondary biocide to prevent soft growth and enhance its antifouling capabilities. White Copper -(Cuprous Thiocyanate)- requires 50% less copper content than the heavy, dark copper used in conventional antifouling paints. They are the only copper-based paints that are compatible with aluminum.
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In modern times, antifouling paints are formulated with cuprous oxide (or other copper compounds) and/or other biocides—special chemicals which impede growth of barnacles, algae, and marine organisms. Historically, copper paints were red, leading to ship bottoms still being painted red today. "Soft", or ablative bottom paints slowly slough off in the water, releasing a copper or zinc based biocide into the water column. The movement of water increases the rate of this action.
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Copper(I) sulfate, also known as cuprous sulfate and dicopper sulfate, is the chemical compound with the chemical formula Cu2SO4 and a molar mass of 223.15 g mol−1. It is an unstable compound as copper(I) compounds are generally unstable and is more commonly found in the CuSO4 state. It is white in color at room temperature and is water-soluble. Due to the low-stability of the compound there are currently not many applications to date.
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The Sandmeyer reaction is a chemical reaction used to synthesize aryl halides from aryl diazonium salts using copper salts as reagents or catalysts. It is an example of a radical-nucleophilic aromatic substitution. The Sandmeyer reaction provides a method through which one can perform unique transformations on benzene, such as halogenation, cyanation, trifluoromethylation, and hydroxylation. :300x300px The reaction was discovered in 1884 by Swiss chemist Traugott Sandmeyer, when he attempted to synthesize phenylacetylene from benzenediazonium chloride and cuprous acetylide.
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A sacrificial layer of a noble metal can be used on the base metal as an oxygen barrier, preventing formation of oxides and facilitating fluxless brazing. During brazing, the noble metal layer dissolves in the filler metal. Copper or nickel plating of stainless steels performs the same function. In brazing copper, a reducing atmosphere (or even a reducing flame) may react with the oxygen residues in the metal, which are present as cuprous oxide inclusions, and cause hydrogen embrittlement.
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Once coordinated, the ligand-metal complex assumes a distorted, trigonal bi-pyramidal geometry that stabilizes the cuprous (Cu(I)) reduced state of the protein relative to the cupric (Cu(II)) oxidized state. Structurally imposed backbonding between the copper d orbitals and its ligand p orbitals may further stabilize the cuprous state. Existing structural information about azurin has largely been derived from X-ray crystallography studies of single-site mutated forms of the protein. Notable structural features elucidated by crystallography include the beta-sandwich motif formed from eight interlocking beta strands, as well as an alpha-helical segment outside the barrel linking beta-sheets 4 and 5. Although the Cu(I)/Cu(II) redox potential is typically higher for azurin than most other copper complexes, structural studies in which Met121 (one of azurin’s equatorial copper-coordinating ligands) is replaced have demonstrated that the absence of a thiolate copper ligand does not preclude high reduction potentials, as large hydrophobic residues in position 121 also raise the redox potential of the copper atom.
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Various materials may be employed as electrodes, various electrolyte are possible and many combinations of these elements have been the object of considerable experimentation. The United States challenged the validity of the Adams patent on the ground of lack of novelty as well as obviousness. The Government argued that wet batteries comprising a zinc anode and silver chloride cathode were old in the art; and that the prior art showed that magnesium could be substituted for zinc and cuprous chloride for silver chloride.
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One problem addressed by mixed cuprates is the economical use of the alkyl group. Thus, in some applications, the mixed cuprate has the formula is prepared by combining thienyllithium and cuprous cyanide followed by the organic group to be transferred. In this higher order mixed cuprate, both the cyanide and thienyl groups do not transfer, only the R group does.Bruce H. Lipshutz, Robert Moretti, Robert Crow "Mixed Higher-order Cyanocuprate-induced Epoxide Openings: 1-Benzyloxy-4-penten-2-ol" Org. Synth.
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Some of their subsequent experiments on thermionic emission provided experimental validation for the Sommerfeld theory. They also did work on the surface state and work function of tungsten and the adsorption of thorium atoms. Through his studies of rectification and photo-effects on the semiconductor surfaces of cuprous oxide and silicon, Brattain discovered the photo-effect at the free surface of a semiconductor. This work was considered by the Nobel prize committee to be one of his chief contributions to solid state physics.
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Evgenii Fedorovich Gross (1897 - 1972) was a Soviet physicist working in optics and spectroscopy of condensed matter. He graduated from Leningrad University in 1924. He became a correspondent member of the USSR Academy of Sciences in 1946. His two key achievements are the experimental observation of the fine structure of Rayleigh scattering line due to Brillouin-Mandelstam light scattering on acoustic waves in condensed matter (1930) and the experimental discovery of the exciton (in semiconductor crystals of cuprous oxide) through evidence of its hydrogen-like optical spectrum.
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Cuprous cyanide is commercially available and is supplied as the low-temperature polymorph. It can be prepared by the reduction of copper(II) sulfate with sodium hydrogensulfite at 60 °C, followed by the addition of sodium cyanide to precipitate pure LT-CuCN as a pale yellow powder. : 2 CuSO4 \+ NaHSO3 \+ H2O + 2 NaCN -> 2 CuCN + 3 NaHSO4 On addition of sodium bisulfite the copper sulfate solution turns from blue to green, at which point the sodium cyanide is added. The reaction is performed under mildly acidic conditions.
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As described originally by Oskar Baudisch in 1939 and further developed by his colleague Cronheim in 1947, benzene, hydroxylamine, and hydrogen peroxide are combined. Baudisch proposed that o-nitrosophenols are formed when a "nitrosyl radical" NOH, inserts a C-H bond followed by the oxygenation at a position ortho to the nitroso group. The nitrosylating agent can be generated from three different nitrogen sources, all requiring presence of hydrogen peroxide: #oxidation of hydroxylamine hydrochloride with cupric ions. #reduction of nitrous acid with cuprous ions.
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A copper pesticide is a copper compound used as a pesticide or fungicide. In the UK the Soil Association (one of the organic certification authorities) permits farmers to use some copper fungicides on organic land used for the production of certified organic crops only if there is a major threat to crops. Section 4.11.11, Soil Association Organic Standards for Producer, Version 16.1, April, 2010 The compounds permitted are copper sulfate, copper hydroxide, cuprous oxide, copper oxychloride, copper ammonium carbonate (at a maximum concentration of 25 g/l), and copper octanoate.
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Typically, alkyl nitriles are formed via SN1 or SN2-type cyanation with alkyl electrophiles. Illustrative is the synthesis of benzyl cyanide by the reaction of benzyl chloride and sodium cyanide. In some cases cuprous cyanide is used instead of sodium cyanide. Cyanation of ketones or aldehydes yields the corresponding cyanohydrins, which can be done directly with the cyanide ion (the cyanohydrin reaction) or by using bisulfate, followed by displacement of sulfite: Cyanation of aldehyde with bisulfate A related reaction is hydrocyanation, which installs the elements of H-CN.
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The Government challenged the validity of the patent and denied that it had been infringed or that any contract for its use had ever existed. The Trial Commissioner held that the patent was valid and infringed in part but that no contract, express or implied, had been established. The United States sought certiorari on the patent validity issue only. The patent under consideration, U.S. No. 2,322,210, relates to a nonrechargeable electrical battery composed of two electrodes - one of magnesium and the other of cuprous chloride, with a plain or salt water electrolyte.
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The sap in these poles acted as the reducing agent. The heat of the copper makes the pole emit wood gas(CO2 and H2) that reduces the cuprous oxide to copper. It was the use of these greenwood poles gave rise to the term "poling." Care must be taken to avoid removing too much of the oxygen from the anode copper, as this will cause other impurities to change from their oxide to metallic states and they will remain in solid solution in the copper, reduce its conductivity and change its physical properties.
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The application of copper fungicide has been shown to significantly reduce a great number of black pod incidences in Nigeria. Metalaxyl (Ridomil) and cuprous oxide (Perenox) were identified to be successful in increasing the number of harvested healthy pod compared to the application of fosetyl aluminium (Aliete) and control treatment. On top of that, the timing of fungicide application has some positive effect on the final pod yield where this plot produced greater yield than the unsprayed plot. The application was done before August, which is before the main disease epidemic that usually occurs in September and October.
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Syngas can be used in the Fischer–Tropsch process to produce diesel, or converted into e.g. methane, methanol, and dimethyl ether in catalytic processes. If the syngas is post-treated by cryogenic processing, it should be taken into account that this technology has great difficulty in recovering pure carbon monoxide if relatively large volumes of nitrogen are present due to carbon monoxide and nitrogen having very similar boiling points which are –191.5 °C and –195.79 °C respectively. Certain process technology selectively removes carbon monoxide by complexation/decomplexation of carbon monoxide with cuprous aluminum chloride () dissolved in an organic liquid such as toluene.
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Bolton saw this as an opportune time to start DuPont research on synthetic rubber. However, this research did not begin in earnest until 1925, when the high price of rubber was attracting considerable attention and other scientists such as Thomas Edison were also taking an interest in the problem. Bolton's group's work on synthetic rubber began with the polymerization of butadiene obtained from the hydrogenation of diacetylene, and at first not much progress was made. At the end of 1925 Bolton met chemist Julius Arthur Nieuwland from the University of Notre Dame who had discovered a way to polymerize acetylene using a cuprous oxide catalyst.
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Libavius was an orthodox Lutheran, and in his theological treatises, which he wrote under the pseudonym of Basilius de Varna, he criticized Catholicism, specifically the Jesuit order, and later on in his life, Calvinism. This can also be seen in some of his non- theological works, particularly in some of the works produced during his involvement with the conflict between the Paracelsists, anti-Paracelsists, Galenists, and Hermetics. In 1597, he wrote the first systematic chemistry textbook, Alchymia, where he described the possibility of transmutation. In this book he also showed that cuprous salt lotions are detectable with ammonia, which causes them to change color to dark blue.
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By the mid-twentieth century, copper oxide-based paints could keep a ship out of drydock for as much as 18 months, or as little as 12 in tropical waters. The shorter service life was due to rapid leaching of the toxicant, and chemical conversion into less toxic salts, which accumulated as a crust that would inhibit further leaching of active cuprous oxide from the layer under the crust. The 1960s brought a breakthrough, with self-polishing paints that used seawater's ability to hydrolize the paint's copolymer bond and release the stored toxin at a slow, controlled rate. These paints employed organotin chemistry ("tin-based") biotoxins such as tributyltin oxide (TBT) and were effective for up to four years.
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Sulfur dioxide is a versatile inert solvent widely used for dissolving highly oxidizing salts. It is also used occasionally as a source of the sulfonyl group in organic synthesis. Treatment of aryl diazonium salts with sulfur dioxide and cuprous chloride yields the corresponding aryl sulfonyl chloride, for example: :upright=2 As a result of its very low Lewis basicity, it is often used as a low-temperature solvent/diluent for superacids like Magic acid (FSO3H/SbF5), allowing for highly reactive species like tert-butyl cation to be observed spectroscopically at low temperature (though tertiary carbocations do react with SO2 above about –30 °C, and even less reactive solvents like SO2ClF must be used at these higher temperatures).
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Karl Wilhelm Sali Baedeker (3 February 1877 - 6 August 1914) was a German physicist, and a professor at the University of Jena. He was the grandson of Karl Baedeker, the founder of the eponymous travel guide publishing house, and the son of Fritz Baedeker (1844 - 1925), who ran the same company from 1869 until his death in 1925. One of his scientific discoveries was that the resistivity of cuprous iodide (CuI) depended on its stoichiometry. Thin films of the material became much more conductive when exposed to iodine vapor; the effect was reversible. This was the first example of doping a semiconductor to change its propertiesJed Z. Buchwald, Andrew Warwick (ed) Histories of the Electron: The Birth of Microphysics MIT Press, 2004 pp.
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Many thiolate complexes are prepared by redox reactions. Organic disulfides oxidize low valence metals, as illustrated by the oxidation of titanocene dicarbonyl: :(C5H5)2Ti(CO)2 \+ (C6H5S)2 → (C5H5)2Ti(SC6H5)2 \+ 2 CO Some metal centers are oxidized by thiols, the coproduct being hydrogen gas: :Fe3(CO)12 \+ 2 C2H5SH → Fe2(SC2H5)2(CO)6 \+ Fe(CO)5 \+ CO + H2 These reactions probably proceed via oxidative addition of the thiol. Thiols and especially thiolate salts are reducing agents. Consequently, they induce redox reactions with certain transition metals. This phenomenon is illustrated by the synthesis of cuprous thiolates from cupric precursors: :4 HSC6H5 \+ 2 CuO → 2 Cu(SC6H5) + (C6H5S)2 \+ 2 H2O Thiolate clusters of the type [Fe4S4(SR)4]2− occur in iron–sulfur proteins.
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Normal (p–n) diodes, which operate as described above, are usually made of doped silicon or germanium. Before the development of silicon power rectifier diodes, cuprous oxide and later selenium was used. Their low efficiency required a much higher forward voltage to be applied (typically 1.4 to 1.7 V per "cell", with multiple cells stacked so as to increase the peak inverse voltage rating for application in high voltage rectifiers), and required a large heat sink (often an extension of the diode's metal substrate), much larger than the later silicon diode of the same current ratings would require. The vast majority of all diodes are the p–n diodes found in CMOS integrated circuits, which include two diodes per pin and many other internal diodes.
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When it was realized that some metals form two different binary compounds with the same nonmetal, the two compounds were often distinguished by using the ending -ic for the higher metal oxidation state and the ending -ous for the lower. For example, FeCl3 is ferric chloride and FeCl2 is ferrous chloride. This system is not very satisfactory (although sometimes still used) because different metals have different oxidation states which have to be learned: ferric and ferrous are +3 and +2 respectively, but cupric and cuprous are +2 and +1, and stannic and stannous are +4 and +2. Also there was no allowance for metals with more than two oxidation states, such as vanadium with oxidation states +2, +3, +4 and +5.
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Firestain is a layer of oxides that is visible on the surface of objects made of metal alloys containing copper when the object is heated, as by a jeweler heating a ring to apply solder during a repair. On copper-containing alloys of gold or of silver (such as sterling silver), it presents as a red or purple stain. This is because at high temperatures, oxygen mixes with the copper to form cuprous oxide and then cupric oxide, both of which disrupt the bright polished surface of the finished piece. It is sometimes referred to incorrectly as 'Firescale'; 'Firescale' is a flaky deposit that can occur on the surface of non ferrous metals when heated, on ferrous metals this is known as Mill scale Attempts to reduce the problem of firestain include preventative and curative ones.
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Much more serious was the problem of elements which form more than one oxide or series of salts, which have (in today's terminology) different oxidation states. Copper will react with oxygen to form either brick red cuprous oxide (copper(I) oxide, with 63.5 g of copper for 8 g of oxygen) or black cupric oxide (copper(II) oxide, with 32.7 g of copper for 8 g of oxygen), and so has two equivalent weights. Supporters of atomic weights could turn to the Dulong–Petit law (1819), which relates the atomic weight of a solid element to its specific heat capacity, to arrive at a unique and unambiguous set of atomic weights. Most supporters of equivalent weights—which were the great majority of chemists prior to 1860—simply ignored the inconvenient fact that most elements exhibited multiple equivalent weights.
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There have been copper prospects operating on Red Mountain 2445 m (8022 ft), the highest in the range, and on Poison Mountain 2264 m (7428 ft), just south Red, is located where the spine of the Shulaps Range intersects with that of the Camelsfoot, at the apex of the Yalakom valley which runs SE towards Lillooet from this point. Poison Mountain's name comes from the toxic leaching of its orebodies into local streams (and rumours of mercury in the copper ore) while Red's comes from the colour of its cuprous earth. Red's flanks show ziggurat-like scars that are evidence of the scale of ore-sampling that at one time was underway. There are projected open-pit mine and smelter plans for the Poison Mountain-Red Mountain orebody, using power from the also projected Hat Creek lignite deposits nearby on the other side of the Fraser.
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Scheme of flash smelting process The concentration of copper in ores averages only 0.6%, and most commercial ores are sulfides, especially chalcopyrite (CuFeS2), bornite (Cu5FeS4) and, to a lesser extent, covellite (CuS) and chalcocite (Cu2S). These minerals are concentrated from crushed ores to the level of 10–15% copper by froth flotation or bioleaching. Heating this material with silica in flash smelting removes much of the iron as slag. The process exploits the greater ease of converting iron sulfides into oxides, which in turn react with the silica to form the silicate slag that floats on top of the heated mass. The resulting copper matte, consisting of Cu2S, is roasted to convert all sulfides into oxides: :2 Cu2S + 3 O2 → 2 Cu2O + 2 SO2 The cuprous oxide is converted to blister copper upon heating: :2 Cu2O → 4 Cu + O2 The Sudbury matte process converted only half the sulfide to oxide and then used this oxide to remove the rest of the sulfur as oxide.
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