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cyanide

cyanide

cyanide Sentence Examples

  • They've been killing themselves with cyanide pills, Rainy added.

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  • They've been killing themselves with cyanide pills, Rainy added.

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  • The cyanide process is especially treated by M.

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  • The cyanide process is especially treated by M.

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  • Eissler, Cyanide Process for the Extraction of Gold, which pays particular attention to the Witwatersrand methods; Alfred James, Cyanide Practice; H.

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  • dissolving the gold in potassium cyanide solution, and then precipitating the metal; 5.

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  • His earlier work included an investigation of succinic acid, and the preparation of phenyl cyanide (benzonitrile), the simplest nitrile of the aromatic series; but later his time was mainly occupied with questions of technology and public health rather than with pure chemistry.

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  • Cyanide Process.

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  • GayLussac, who obtained it by heating mercury or silver cyanide; this discovery is of considerable historical importance, since it recorded the isolation of a "compound radical."

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  • The precipitated tellurium is then fused with potassium cyanide, the melt extracted with water and the element precipitated by drawing a current of air through the solution and finally distilled in a current of hydrogen.

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  • The precipitated tellurium is then fused with potassium cyanide, the melt extracted with water and the element precipitated by drawing a current of air through the solution and finally distilled in a current of hydrogen.

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  • For this reason the acid copper-bath is not used for iron or zinc objects, a bath containing copper cyanide or oxide dissolved in potassium cyanide being substituted.

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  • For this reason the acid copper-bath is not used for iron or zinc objects, a bath containing copper cyanide or oxide dissolved in potassium cyanide being substituted.

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  • By the cyanide process, i.e.

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  • When xylose is combined with hydrocyanic acid and the cyanide is hydrolysed, together with l-gulonic acid, a second isomeric acid, l-idonic acid, is produced, which on reduction yields the hexaldose l-idose.

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  • When xylose is combined with hydrocyanic acid and the cyanide is hydrolysed, together with l-gulonic acid, a second isomeric acid, l-idonic acid, is produced, which on reduction yields the hexaldose l-idose.

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  • the chlorination or Plattner process, in which the metal is converted into the chloride, and the cyanide or MacArthur-Forrest process, in which it is converted into potassium aurocyanide.

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  • Grease must be removed by potash, whiting or other means, and tarnish by an acid or potassium cyanide, washing in plenty of water being resorted to after each operation.

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  • The addition of potassium cyanide has been suggested to assist the amalgamation and to prevent " flouring," but Skey has shown that its use is attended with loss of gold.

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  • Auric cyanide, Au(CN) 3, is not certainly known; its double salts, however, have been frequently described.

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  • Auric cyanide, Au(CN) 3, is not certainly known; its double salts, however, have been frequently described.

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  • It is insoluble in dilute acids, but is readily soluble in excess of potassium cyanide.

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  • By dry distillation it gives ammonium cyanide.

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  • Pyruvic nitrile, or acetyl cyanide, CH 3 CO.

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  • It can also be prepared by heating borimide B2(NH)31 or by heating boron trioxide with a metallic cyanide.

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  • Many esters of malonic acid have been prepared, the most important being the diethyl ester (malonic ester), CH 2 (000C 2 H 5) 2, which is obtained by dissolving monochloracetic acid in water, neutralizing the solution with potassium carbonate, and then adding potassium cyanide and warming the mixture until the reaction begins.

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  • The half nitrile of malonic acid is cyanacetic acid, CN CH 2 COOH, which, in the form of its ester, may be obtained by the action of a solution of potassium cyanide on monochloracetic acid.

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  • The true nitrile of malonic acid is methylene cyanide, CH 2 (CN) 2, which is obtained by distilling a mixture of cyanacetamide and phosphorus pentoxide.

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  • An interesting example of secondary action is shown by the common technical process of electroplating with silver from a bath of potassium silver cyanide.

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  • (I) Commercially pure tin is treated with nitric acid, which converts the tin proper into the insoluble metastannic acid, while the copper, iron, &c., become nitrates; the metastannic acid is washed first with dilute nitric acid, then with water, and is lastly dried and reduced by fusion with black flux or potassium cyanide.

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  • It is also obtained by the action of hydrogen peroxide on hydrocyanic acid, or of manganese dioxide and sulphuric acid on potassium cyanide.

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  • This salt is prepared by precipitating a solution of gold in aqua regia by ammonia, and then introducing the well-washed precipitate into a boiling solution of potassium cyanide.

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  • Potassium auricyanide, 2KAu(CN) 4.3H 2 O, is obtained as large, colourless, efflorescent tablets by crystallizing concentrated solutions of auric chloride and potassium cyanide.

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  • 19) the rate of solution in potassium cyanide depends upon the subdivision of the gold - the finer the subdivision the quicker the solution, - and on the concentration of the solution - the rate increasing until the solution contains 0.25% of cyanide, and remaining fairly stationary with increasing concentration.

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  • Its advantages over the zinc process are that the deposited gold is purer and more readily extracted, and that weaker solutions can be employed, thereby effecting an economy in cyanide.

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  • Heavy blanks have also been reduced chemically by making them part of the anode in a cyanide bath through which a current of electricity is passed.

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  • The cyanide process of gold extraction, and the returns obtained by its means from the great Waihi mine in the Upper Thames, caused an outbreak of gold fever, which led to the opening up of a few good and a great many worthless quartz-mines in the Auckland fields.

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  • For sodium nitrite see Nitrogen; for sodium nitrate see Saltpetre; for the cyanide see Prussic Acid; and for the borate see Borax.

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  • There are smelters and cyanide extracters in the district, but the bulk of the ore product is shipped to other places for treatment.

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  • For the nitrite, see Nitrogen, for the nitrate see Saltpetre and for the cyanide see Prussic Acid; for other salts see the articles wherein the corresponding acid receives treatment.

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  • Those of the heavy metals are mostly insoluble in water, but are soluble in a solution of potassium cyanide, forming more or less stable double salts, for example KAg(NC)2, KAu(NC) 2.

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  • Lead cyanide, Pb(NC) 2, however, does not form such a salt, and is insoluble in potassium cyanide solution.

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  • Ammonium cyanide, NH 4 NC, a white solid found to some slight extent in illuminating gas, is easily soluble in water and alcohol, and is very poisonous.

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  • It is obtained by passing ammonia gas over hot coal; by subliming a mixture of ammonium chloride and potassium cyanide; by passing a mixture of ammonia gas and chloroform vapour through a red hot tube; and by heating a mixture of ammonia and carbon monoxide: CO+2NH 3 = NH 4 NC+H 2 0.

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  • Barium cyanide, Ba(NC) 2, prepared by the action of potassium cyanide on baryta, or by passing air over a heated mixture of barium carbonate and coal, is a white solid, which when heated with water to 300° C. loses the whole of its nitrogen in the form of ammonia.

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  • Mercuric cyanide, Hg(NC)2, is a sparingly soluble salt formed by dissolving precipitated mercuric oxide in hydrocyanic acid, or by boiling potassium ferrocyanide with mercuric sulphate and water: 2K4Fe(NC)6+3HgS04=3Hg(NC)2+ 3K 2 SO 4 -{-K 2 Fe[Fe(NC) 6 ].

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  • Silver cyanide, AgNC, is formed as a white precipitate by adding potassium cyanide to silver nitrate solution; or better, by adding silver nitrate to potassium silver cyanide, KAg(NC) 2, this double cyanide being obtained by the addition of one molecular proportion of potassium cyanide to one molecular proportion of silver nitrate, the white precipitate so formed being then dissolved by adding a second equivalent of potassium cyanide.

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  • Dilute mineral acids decompose it with the formation of insoluble silver cyanide and hydrocyanic acid: KNC AgNC+HN03=HCN+ KNO 3 +AgNC. A boiling solution of potassium chloride with the double cyanide gives silver chloride and potassium cyanide.

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  • Potassium cyanide, KNC, and sodium cyanide, NaNC, are two of the most important of the salts of hydrocyanic acid, the former being manufactured in large quantities for consumption in the extraction of gold.

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  • Potassium cyanide may be obtained by fusing potassium ferrocyanide either alone - K4Fe(NC)6=4KNC+ FeC2+N2 - or with potassium carbonate [V.

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  • Rossler and Hasslacher prepare the double potassium sodium cyanide by fusing potassium ferrocyanide with sodium, the product of fusion being extracted with water and the solution evaporated: K 4 Fe(NC) 6 +2Na = Fe+ 4KNC 2NaNC. This process gives a product free from cyanate, which was always formed in the older fusion processes.

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  • 33 28, 3329 (1901)] prepare sodium cyanamide by melting sodium with carbons or some hydrocarbon, and passing ammonia over the melt at from 400 0 -600° C. The temperature is then raised to 700°-800° C., and the sodium cyanamide in contact with the residual carbon forms sodium cyanide.

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  • Potassium cyanide is an excessively poisonous, colourless, deliquescent solid; it is readily soluble in water, but almost insoluble in absolute alcohol.

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  • The double cyanides formed by the solution of the cyanide of a heavy metal in a solution of potassium cyanide are decomposed by mineral acids with liberation of hydrocyanic acid and formation of the cyanide of the heavy metal.

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  • Potassium ferrocyanide, K 4 Fe(NC) 6, (yellow prussiate of potash), was first obtained by decomposing Prussian blue with caustic potash: Fe4[Fe(NC)6]3 + 12KHO = 3K 4 Fe(NC) 6 +4Fe(OH) 3; it may be also obtained by warming a solution of ferrous sulphate with an excess of potassium cyanide: FeS04-I-6KNC = K4Fe(NC)6+ K2S04.

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  • When fused with potassium carbonate it yields potassium cyanide; warmed with dilute sulphuric acid it yields hydrocyanic acid, but with concentrated sulphuric acid it yields carbon monoxide: 6H 2 O + K 4 Fe(NC) 6 + 6H 2 SO 4 = 2K 2 SO 4 + FeSO 4 + 3(NH4)2S04 + 6C0.

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  • The potassium salt may be prepared by adding potassium cyanide to ferrous sulphate solution, the brown precipitate so formed being then heated with potassium nitrite: 5 KNC + 2 FeSO 4 = 2 K 2 SO 4 + KFe2(NC)5, 2 KFe 2 (NC) 5 + 2 KNO 2 = 2 FeO + 2 K2Fe(NC)5 NO.

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  • Allyl cyanide boils at 119° C. Benzonitrile boils at 190.6° C. When solidified it melts att7° C. It is easily soluble in alcohol and ether.

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  • Gautier (Ann., 1869, 151, p. 239) by the action of alkyl iodides on silver cyanide, and the distillation of the resulting compound with potassium cyanide in concentrated aqueous solution: RIR Ag(NC) 2 -)R NC+KAg(NC)2.

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  • - Considerable discussion has taken place as to the structure of the metallic cyanides, since potassium cyanide and silver cyanide react with alkyl iodides to form nitriles and isonitriles respectively, thus apparently pointing to the fact that these two compounds possess the formulae KCN and AgNC. The metallic cyanides are analogous to the alkyl isocyanides, since they form soluble double silver salts, and the fact that ethyl ferrocyanide on distillation yields ethyl isocyanide also points to their isocyanide structure.

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  • On the other hand, when there is but little electro-chemical difference between the radical of the cyanide and that of the reacting compound then the nitrogen atom is the more unsaturated element and.

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  • As an alternative test the cyanide may be decomposed by dilute hydrochloric acid, and the liberated hydrocyanic acid absorbed in a little yellow ammonium sulphide.

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  • Silver nitrate gives a white precipitate with cyanides, soluble in excess of potassium cyanide.

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  • Lengler, The Cyanide Industry, 1906 (Eng.

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  • Cyanogen compounds of chromium, analogous to those of iron, have been prepared; thus potassium chromocyanide, K 4 Cr(CN) 6.2H 2 0, is formed from potassium cyanide and chromous acetate; on exposure to air it is converted into the chromicyanide, K 3 Cr(CN) 6, which can also be prepared by adding chromic acetate solution to boiling potassium cyanide solution.

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  • Diazobenzenecyanide, C 6 H 5 N 2 CN, is an unstable oil, formed when potassium cyanide is added to a solution of a diazonium salt.

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  • Crotonic acid, so named from the fact that it was erroneously supposed to be a saponification product of croton oil, may be prepared by the oxidation of croton-aldehyde, CH3 CH:CH CHO, obtained by dehydrating aldol, or by treating acetylene successively with sulphuric acid and water; by boiling allyl cyanide with caustic potash; by the distillation of 0-oxybutyric acid; by heating paraldehyde with malonic acid and acetic acid to, oo C. (T.

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  • Cannizzaro); and on warming with alcoholic potassium cyanide it condenses to benzoin.

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  • It may also be prepared by heating a mixture of carbon, oxide of iron and magnesite to bright redness; and by heating a mixture of magnesium ferrocyanide and sodium carbonate, the double cyanide formed being then decomposed by heating it with metallic zinc. Electrolytic methods have entirely superseded the older methods.

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  • a-Naphthoic acid, C 1 oH 7 CO 2 H, is formed by hydrolysis of the nitrile, obtained by distilling potassiuma-naphthalene sulphonate with potassium cyanide (V.

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  • In the case of iodine, the substitution is effected by adding a warm solution of potassium iodide to the diazonium solution, no copper or cuprous salt being necessary; whilst for the production of nitriles a solution of potassium cuprous cyanide is used.

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  • By diazotizing para-chloraniline and adding a cold solution of potassium cyanide, a salt (melting at 29° C.) is obtained, which readily loses nitrogen, and forms parachlorbenzonitrile on the addition of copper powder.

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  • Similar results have been obtained by using diazotized para-anisidine, a synand an anticompound being formed, as well as a third isomeric cyanide, obtained by evaporating para-methoxybenzenediazonium hydroxide in the presence of an excess of hydrocyanic acid at ordinary temperatures.

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  • p. 543), as has also aluminium turnings moistened with potassium cyanide and mercuric chloride, which decomposes water regularly at 70°, i gram giving 1.3 litres of gas (Mauricheau-Beaupre, Comptes rendus, 1908, 147, p. 310).

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  • It is of value in cyanide and opium poisoning and in the resuscitation of the apparently drowned.

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  • Numerous methods have been devised for the separation of nickel and cobalt, the more important of which are: -the cobaltinitrite method by which the cobalt is precipitated in the presence of acetic acid by means of potassium nitrite (the alkaline earth metals must not be present); the cyanide method (J.

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  • Liebig, Ann., 1848, 6 5, p. 2 44; 1853, 87, p.128), in which the two metals are precipitated by excess of potassium cyanide in alkaline solution, bromine being afterwards added and the solution warmed, when the nickel is precipitated.

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  • The latter method has been modified by adding potassium cyanide in slight excess to the solution of the mixed salts, heating for some time and then adding mercuric oxide and water, the whole being then warmed on the water bath, when a precipitate of mercuric oxide and nickel hydroxide is obtained 666, 670).

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  • Succinonitrile, C2H4(CN)2r is obtained by the action of potassium cyanide on ethylene dibromide or by the electrolysis of a solution of potassium cyanacetate.

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  • The cyanide process, introduced about 1890, is now one of the most important factors in the utilization of low-grade and refractory gold and silver ores.

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  • The improved dioxide cyanide process was adopted about 1895.

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  • It may be detected by the addition of an aqueous solution of potassium cyanide, with which it gives a violet-red coloration, due to the formation of isopurpuric acid.

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  • It is decomposed by water with evolution of hydrogen, and on heating in a current of carbonic oxide forms barium cyanide (L.

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  • The potassium cyanide method is based on the fact that, when potassium cyanide is added to an ammoniacal solution of a salt of copper, the insoluble copper cyanide is formed, the end of the reaction being indicated by the disappearance of the blue colour of the solution.

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  • To the filtrate (or, if no silver is present, to the diluted nitric acid solution) io cc. of ammonia are added, and a standard solution of potassium cyanide is run in from a burette until the blue colour has nearly disappeared.

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  • The potassium cyanide solution is standardized by dissolving 0.5 gramme o£ pure copper in 5 cc. of nitric acid, diluting, adding io cc. of ammonia, and titrating exactly as described above.

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  • The ore is treated as described in the cyanide method until the copper precipitated by the aluminium foil has been washed and dissolved in 5 cc. of nitric acid; then 0.25 gramme of potassium chlorate is added, and the solution boiled nearly dry to oxidize any arsenic present to arsenic acid.

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  • Sodium chloride, characteristic of the Augustin process in which the ores, after a chloridizing roast, were extracted with brine, and the silver precipitated by copper, has almost wholly fallen into disuse; and potassium cyanide, which has become a very important solvent for finely divided gold, is rarely used in leaching silver ores.

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  • It readily dissolves in ammonia, the solution, on evaporation, yielding rhombic crystals of 2AgC1.3NH 3; it also dissolves in sodium thiosulphate and potassium cyanide solutions.

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  • Nilson (Ber., 1874, 7, p. 1719) digests the well-washed chamber mud with a moderately concentrated solution of potassium cyanide, whereby the element goes into solution in the form of potassium selenocyanide, KSe(CN), from which it is precipitated by hydrochloric acid.

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  • It is also obtained when dry ammonia gas is passed into a dilute solution of selenyl chloride in benzene, the precipitate produced being digested with potassium cyanide to remove any selenium (V.

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  • It is a brickred powder which explodes when heated to 130° C. Selenium cyanide, Se(CN) 2, is obtained by decomposing silver selenocyanide with cyanogen iodide, or by the action of silver cyanide on a solution of selenium bromide in carbon bisulphide.

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  • A more complex cyanide, Se3(CN)2, is obtained by passing a current of chlorine and air into an aqueous solution of potassium selenocyanide (A.

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  • When heated to 180° C. in vacuo it yields the simple cyanide Se(CN) 2.

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  • Potassium selenocyanide, KSeCN, is obtained by the action of selenium on a concentrated aqueous solution of potassium cyanide, or by heating selenium with anhydrous potassium ferrocyanide (W.

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  • Meyer (Ber., 1902, 35, p. 1 59 1) by the electrolysis of silver selenite in the presence of potassium cyanide obtained the value 79.22.

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  • of Great Salt Lake) whose ores are reduced by the cyanide process.

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  • Cyanogen compounds also are present in the gas, and in large works, where the total quantity is sufficient, their extraction is effected for the production of either prussiate or cyanide of soda.

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  • Cyanogen compounds are extracted either direct from the gas, from the spent oxide or from ammoniacal liquor, and some large gas works now produce sodium cyanide, this being one of the latest developments in the gas chemical industry.

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  • CO 2 H,with sodium amalgam, by conversion of trimethylene bromide into the cyanide and hydrolysis of this compound, or from acetoacetic ester, which, in the form of its sodium derivative, condenses with j3-iodopropionic ester to form acetoglutaric ester, CH 3 CO CH(CO 2 C 2 H 5) CH 2.

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  • Adolf Hitler used Blondi to make sure cyanide capsules were lethal.

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  • cyanide of potassium, a deadly poison, which he gave to Sarah in a glass of stout.

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  • The cleaner does not contain any cyanide or environmentally unfriendly detergent compounds.

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  • The majority of them are stunned by divers who use cyanide to poison the waters around them.

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  • He died in 1954 from taking potassium cyanide at his home where he was performing electrolysis experiments.

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  • A cigarette butt contains up to 4,000 chemicals, including hydrogen cyanide and arsenic.

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  • Police said no cyanide or noxious gas had been found on the men when they were arrested on 9 November.

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  • Smokers should note that the cyanide absorbed from the smoke into the blood causes the replacement of the 5'-deoxyadenosyl group by a cyanide absorbed from the smoke into the blood causes the replacement of the 5'-deoxyadenosyl group by a cyanide.

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  • cyanide in water is quite alkaline, and contains significant amounts of hydroxide ions.

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  • cyanide poisoning.

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  • cyanide capsules through that roof.

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  • The cyanide ion comes from hydrogen cyanide ion comes from hydrogen cyanide, which is a covalent molecule.

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  • cyanide toxicity.

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  • cyanide compounds.

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  • cyanide pills now.

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  • The cyanide ion comes from hydrogen cyanide, which is a covalent molecule.

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  • Death was clearly caused by taking a very large quantity of potassium cyanide.

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  • You could tolerate the dreaded sodium cyanide at many millions of times the concentration.

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  • The old name for this would have been methyl cyanide.

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  • Applications so far include the determination of blood cyanide and the generation of oxygen radicals.

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  • cyanogens chloride or hydrogen cyanide.

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  • Iraq didn't need to use hydrogen cyanide directly in order to produce blue discoloration around mouths.

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  • hydrogen cyanide Hydrogen cyanide is the third constituent of nicotine thought to impair wound healing in cigarette smokers.

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  • laced with cyanide, leading to the deaths of seven customers.

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  • plasma lactate measured at the time of admission has been shown to correlate with cyanide toxicity.

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  • phial vial of cyanide was found in the lining of his jacket.

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  • He died in 1954 from taking potassium cyanide at his home where he was performing electrolysis experiments.

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  • potassium cyanide in water is quite alkaline, and contains significant amounts of hydroxide ions.

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  • Blood gases, like Hydrogen Cyanide, interfere with cell respiration.

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  • The group has told recent visitors to its enclave that it holds stocks of the deadly chemical agents ricin, cyanide gas and aflatoxin.

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  • On the addition of potassium cyanide they give a brown precipitate of cobalt cyanide, Co(CN) 2, which dissolves in excess of potassium cyanide to a green solution.

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  • Cobaltous cyanide, Co(CN)2.3H20, is obtained when the carbonate is dissolved in hydrocyanic acid or when the acetate is precipitated by potassium cyanide.

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  • It is insoluble in dilute acids, but is readily soluble in excess of potassium cyanide.

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  • Hydrocobaltocyanic acid is not known, but its potassium salt, K4Co(CN) 6, is formed when freshly precipitated cobalt cyanide is dissolved in an ice-cold solution of potassium cyanide.

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  • In alkaline solution it readily takes up oxygen and is converted into potassium cobalticyanide, K 3 Co(CN) 6, which may also be obtained by evaporating a solution of cobalt cyanide, in excess of potassium cyanide, in the presence of air, 8KCN+2Co(CN)2+H20+0= 2K 3 Co(CN) 6 +2KHO.

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  • By dry distillation it gives ammonium cyanide.

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  • GayLussac, who obtained it by heating mercury or silver cyanide; this discovery is of considerable historical importance, since it recorded the isolation of a "compound radical."

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  • p. 299), or by the addition of a concentrated solution of potassium cyanide to one of copper sulphate, the mixed solutions being then heated.

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  • When cyanogen is prepared by heating mercuric cyanide, a residue known as para-cyanogen, (CN)x, is left; this is to be regarded as a polymer of cyanogen.

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  • Potash solution converts it into a mixture of potassium cyanide and cyanate.

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  • It may be prepared by boiling a-dichlorpropionic acid with silver oxide; by the hydrolysis of acetyl cyanide with hydrochloric acid (J.

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  • Pyruvic nitrile, or acetyl cyanide, CH 3 CO.

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  • CN, may be prepared by the action of silver cyanide on acetyl chloride; or of acetyl chloride on nitrosoacetone (L.

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  • It can also be prepared by heating borimide B2(NH)31 or by heating boron trioxide with a metallic cyanide.

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  • Chem., 1891, I, p. 364), by the electrolytic reduction of cadmium oxide in potassium cyanide solution, obtained as a mean value 112.055.

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  • The Poisons and Pharmacy Act of 1908 extended the schedule of poisons instituted by the act of 1868, and it now includes arsenic, aconite, aconitine and their preparations; all poisonous vegetable alkaloids, and their salts and poisonous derivatives; atropine and its salts and their preparations; belladonna and all preparations or admixtures (except belladonna plasters) containing 0.1% or more of belladonna alkaloid; cantharides and its poisonous derivatives; any preparation or admixture of coca-leaves containing 0.1% or more of coca alkaloids; corrosive sublimate; cyanide of potassium and all poisonous cyanides and their preparations; tartar emetic, nux vomica, and all preparations or admixtures containing 0.2% or more of strychnine; opium and all preparations and admixtures containing 1% or more of morphine; picro-toxine; prussic acid and all preparations and admixtures containing o i% or more of prussic acid; savin and its oil, and all preparations or admixtures containing savin or its oil.

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  • The yield reached its lowest point in 1899, but subsequently increased through the application of improved machinery, while the tailings of the old diggings were treated by the cyanide process with profitable results.

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  • Many esters of malonic acid have been prepared, the most important being the diethyl ester (malonic ester), CH 2 (000C 2 H 5) 2, which is obtained by dissolving monochloracetic acid in water, neutralizing the solution with potassium carbonate, and then adding potassium cyanide and warming the mixture until the reaction begins.

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  • The half nitrile of malonic acid is cyanacetic acid, CN CH 2 COOH, which, in the form of its ester, may be obtained by the action of a solution of potassium cyanide on monochloracetic acid.

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  • The true nitrile of malonic acid is methylene cyanide, CH 2 (CN) 2, which is obtained by distilling a mixture of cyanacetamide and phosphorus pentoxide.

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  • Potassium cyanide reacts with this acid to form the corresponding dinitrile, which is converted by hydrochloric acid into citric acid.

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  • Held synthesized the acid from ethyl chlor-acetoacetate (from chlorine and acetoacetic ester) by heating with potassium cyanide and saponifying the resulting nitrile.

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  • Potassium ruthenium cyanide, K4Ru(CN) 6.3H 2 O, formed when potassium ruthenate is boiled with a solution of potassium cyanide, crystallizes in colourless plates which are soluble in water.

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  • Filter from the bismuth hydrate, and if copper is present, add potassium cyanide till the colour is destroyed, then pass sulphuretted hydrogen, and cadmium is precipitated as the yellow sulphide.

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  • In the first group, we have to notice the titration of a cyanide with silver nitrate, when a milkiness shows how far the reaction has gone; the titration of iron with permanganate, when the faint pink colour shows that all the iron is oxidized.

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  • A blue coloration indicates nitrogen, and is due to the formation of potassium (or sodium) cyanide during the fusion, and subsequent interaction with the iron salts.

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  • His earlier work included an investigation of succinic acid, and the preparation of phenyl cyanide (benzonitrile), the simplest nitrile of the aromatic series; but later his time was mainly occupied with questions of technology and public health rather than with pure chemistry.

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  • An interesting example of secondary action is shown by the common technical process of electroplating with silver from a bath of potassium silver cyanide.

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  • Here the ions are potassium and the group Ag(CN)2.1 Each potassium ion as it reaches the cathode precipitates silver by reacting with the solution in accordance with the chemical equation K--+KAg(CN) 2 =2KCN+Ag, while the anion Ag(CN) 2 dissolves an atom of silver from the anode, and re-forms the complex cyanide KAg(CN) 2 by combining with the 2KCN produced in the reaction described in the equation.

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  • If the anode consist of platinum, cyanogen gas is evolved thereat from the anion Ag(CN) 2, and the platinum becomes covered with the insoluble silver cyanide, AgCN, which soon stops the current.

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  • 43) has found that solutions of diphenylamine in methyl cyanide possess an excess of pressure-producing particles and yet are non-conductors of electricity.

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  • The concentration of the simple copper ions is then so much diminished that the copper plate becomes an anode with regard to zinc. Thus the cell - copper I potassium cyanide solution I potassium sulphate solution - zinc sulphate solution I zinc - gives a current which carries copper into solution and deposits zinc. In a similar way silver could be made to act as anode with respect to cadmium.

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  • Grease must be removed by potash, whiting or other means, and tarnish by an acid or potassium cyanide, washing in plenty of water being resorted to after each operation.

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  • Zinc is commonly deposited by electrolysis on iron or steel goods which would ordinarily be "galvanized," but which for any reason may not conveniently be treated by the method of immersion in fused zinc. The zinc cyanide bath may be used for small objects, but for heavy goods the sulphate bath is employed.

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  • When heated with alcoholic potassium cyanide they are converted into benzoins.

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  • Thiele, Ann., 1898, 302, p. 299): HN:CC NH NH2 OC C 6 H 5 NH N + -> HN:CC C C6 H 5 NH 2 OC C6H5 N = C/-C6H5 Wolff has obtained a chloro-derivative by the action of potassium cyanide on diazoacetophenone and subsequent treatment with acid.

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  • (I) Commercially pure tin is treated with nitric acid, which converts the tin proper into the insoluble metastannic acid, while the copper, iron, &c., become nitrates; the metastannic acid is washed first with dilute nitric acid, then with water, and is lastly dried and reduced by fusion with black flux or potassium cyanide.

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  • Tin compounds when heated on charcoal with sodium carbonate or potassium cyanide in the reducing blowpipe flame yield the metal and a scanty ring of white Sn02.

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  • Further work on cyanogen and connected substances yielded a great number of interesting derivatives, and he described an improved method for the manufacture of potassium cyanide, an agent which has since proved of enormous value in metallurgy and the arts.

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  • This view had currency until 1849, when Wohler showed that the crystals are a compound, Ti(CN)2.3T13N2, of a cyanide and a nitride of the metal.

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  • Titanic oxides when fused on charcoal, even with potassium cyanide, yield no metal.

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  • NH 2, is prepared by reducing trimethylene cyanide in ether solution by zinc and hydrochloric acid (A.

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  • CYANIDE, in chemistry, a salt of prussic or hydrocyanic acid, the name being more usually restricted to inorganic salts, i.e.

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  • The most important cyanide commercially is potassium cyanide, which receives application in the "cyanide process" of gold extraction (see Gold).

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  • It is also obtained by the action of hydrogen peroxide on hydrocyanic acid, or of manganese dioxide and sulphuric acid on potassium cyanide.

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  • Aurous cyanide, AuCN, forms yellow, microscopic, hexagonal tables, insoluble in water, and is obtained by the addition of hydrochloric acid to a solution of potassium aurocyanide, KAu(CN)2.

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  • This salt is prepared by precipitating a solution of gold in aqua regia by ammonia, and then introducing the well-washed precipitate into a boiling solution of potassium cyanide.

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  • It is also obtained in the action of potassium cyanide on gold in the presence of air, a reaction utilized in the MacArthur-Forrest process of gold extraction (see below).

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  • Potassium auricyanide, 2KAu(CN) 4.3H 2 O, is obtained as large, colourless, efflorescent tablets by crystallizing concentrated solutions of auric chloride and potassium cyanide.

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  • By the cyanide process, i.e.

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  • dissolving the gold in potassium cyanide solution, and then precipitating the metal; 5.

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  • The addition of potassium cyanide has been suggested to assist the amalgamation and to prevent " flouring," but Skey has shown that its use is attended with loss of gold.

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  • the chlorination or Plattner process, in which the metal is converted into the chloride, and the cyanide or MacArthur-Forrest process, in which it is converted into potassium aurocyanide.

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  • Cyanide Process.

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  • - This process depends upon the solubility of gold in a dilute solution of potassium cyanide in the presence of air (or some other oxidizing agent), and the subsequent precipitation of the gold by metallic zinc or by.

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  • The solubility of gold in cyanide solutions was known to K.

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  • 19) the rate of solution in potassium cyanide depends upon the subdivision of the gold - the finer the subdivision the quicker the solution, - and on the concentration of the solution - the rate increasing until the solution contains 0.25% of cyanide, and remaining fairly stationary with increasing concentration.

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  • The action proceeds in two stages; in the first hydrogen peroxide and potassium aurocyanide are formed, and in the second the hydrogen peroxide oxidizes a further quantity of gold and potassium cyanide to aurocyanide, thus (1) 2Au+4KCN +02+2H20=2KAu(CN)2+4KOH+H202;(2)2Au+4KCN+2H202= 2KAu(CN) 2 +4KOH.

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  • In the Transvaal the operation occupies 32 to 4 days for fine sands, and up to 14 days for coarse sands; the quantity of cyanide per ton of tailings varies from 0.26 to 0.28 lb, for electrolytic precipitation, and o 5 lb for zinc precipitation.

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  • According to Christy, the precipitation with zinc follows equations for 2 according as potassium cyanide is present or not: (1) 4 KAu(CN)2+4Zn+2H20=2Zn(CN)2+ K 2 Zn(CN) 4 +Zn(OK) 2 +4H+4Au; (2) 2KAu (CN) 2 +3Zn+4KCN+2H 2 0 = 2K 2 Zn(CN) 4 +Zn(OK) 2 +4H+2Au; one part of zinc precipitating 3.1 parts of gold in the first case, and 2.06 in the second.

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  • It may be noticed that the potassium zinc cyanide is useless in gold extraction, for it neither dissolves gold nor can potassium cyanide be regenerated from it.

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  • - The electrolytic separation of the gold from cyanide solutions was first practised in the Transvaal.

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  • Its advantages over the zinc process are that the deposited gold is purer and more readily extracted, and that weaker solutions can be employed, thereby effecting an economy in cyanide.

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  • In the process employed at the Worcester Works in the Transvaal, the liquors, containing about 150 grains of gold per ton and from 0.08 to o 01% of cyanide, are treated in rectangular vats in which is placed a series of iron and leaden plates at intervals of 1 in.

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  • A cyanide bath, as used in electroplating, would dissolve the gold, but is not suitable for refining, because other metals (silver, copper, &c.) passing with gold into the solution would deposit with it.

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  • Eissler, Cyanide Process for the Extraction of Gold, which pays particular attention to the Witwatersrand methods; Alfred James, Cyanide Practice; H.

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  • Heavy blanks have also been reduced chemically by making them part of the anode in a cyanide bath through which a current of electricity is passed.

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  • The cyanide process of gold extraction, and the returns obtained by its means from the great Waihi mine in the Upper Thames, caused an outbreak of gold fever, which led to the opening up of a few good and a great many worthless quartz-mines in the Auckland fields.

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  • For sodium nitrite see Nitrogen; for sodium nitrate see Saltpetre; for the cyanide see Prussic Acid; and for the borate see Borax.

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  • There are smelters and cyanide extracters in the district, but the bulk of the ore product is shipped to other places for treatment.

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  • Chem., 1858, 73, p. 413) obtained the metal on a small scale by electrolysing potassium cyanide between carbon electrodes; A.

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  • For the nitrite, see Nitrogen, for the nitrate see Saltpetre and for the cyanide see Prussic Acid; for other salts see the articles wherein the corresponding acid receives treatment.

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  • Those of the heavy metals are mostly insoluble in water, but are soluble in a solution of potassium cyanide, forming more or less stable double salts, for example KAg(NC)2, KAu(NC) 2.

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  • Lead cyanide, Pb(NC) 2, however, does not form such a salt, and is insoluble in potassium cyanide solution.

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  • Ammonium cyanide, NH 4 NC, a white solid found to some slight extent in illuminating gas, is easily soluble in water and alcohol, and is very poisonous.

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  • It is obtained by passing ammonia gas over hot coal; by subliming a mixture of ammonium chloride and potassium cyanide; by passing a mixture of ammonia gas and chloroform vapour through a red hot tube; and by heating a mixture of ammonia and carbon monoxide: CO+2NH 3 = NH 4 NC+H 2 0.

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  • Barium cyanide, Ba(NC) 2, prepared by the action of potassium cyanide on baryta, or by passing air over a heated mixture of barium carbonate and coal, is a white solid, which when heated with water to 300° C. loses the whole of its nitrogen in the form of ammonia.

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  • Mercuric cyanide, Hg(NC)2, is a sparingly soluble salt formed by dissolving precipitated mercuric oxide in hydrocyanic acid, or by boiling potassium ferrocyanide with mercuric sulphate and water: 2K4Fe(NC)6+3HgS04=3Hg(NC)2+ 3K 2 SO 4 -{-K 2 Fe[Fe(NC) 6 ].

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  • Silver cyanide, AgNC, is formed as a white precipitate by adding potassium cyanide to silver nitrate solution; or better, by adding silver nitrate to potassium silver cyanide, KAg(NC) 2, this double cyanide being obtained by the addition of one molecular proportion of potassium cyanide to one molecular proportion of silver nitrate, the white precipitate so formed being then dissolved by adding a second equivalent of potassium cyanide.

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  • Dilute mineral acids decompose it with the formation of insoluble silver cyanide and hydrocyanic acid: KNC AgNC+HN03=HCN+ KNO 3 +AgNC. A boiling solution of potassium chloride with the double cyanide gives silver chloride and potassium cyanide.

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  • Potassium cyanide, KNC, and sodium cyanide, NaNC, are two of the most important of the salts of hydrocyanic acid, the former being manufactured in large quantities for consumption in the extraction of gold.

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  • Potassium cyanide may be obtained by fusing potassium ferrocyanide either alone - K4Fe(NC)6=4KNC+ FeC2+N2 - or with potassium carbonate [V.

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  • Rossler and Hasslacher prepare the double potassium sodium cyanide by fusing potassium ferrocyanide with sodium, the product of fusion being extracted with water and the solution evaporated: K 4 Fe(NC) 6 +2Na = Fe+ 4KNC 2NaNC. This process gives a product free from cyanate, which was always formed in the older fusion processes.

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  • 33 28, 3329 (1901)] prepare sodium cyanamide by melting sodium with carbons or some hydrocarbon, and passing ammonia over the melt at from 400 0 -600° C. The temperature is then raised to 700°-800° C., and the sodium cyanamide in contact with the residual carbon forms sodium cyanide.

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  • Potassium cyanide is an excessively poisonous, colourless, deliquescent solid; it is readily soluble in water, but almost insoluble in absolute alcohol.

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  • The double cyanides formed by the solution of the cyanide of a heavy metal in a solution of potassium cyanide are decomposed by mineral acids with liberation of hydrocyanic acid and formation of the cyanide of the heavy metal.

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  • Potassium ferrocyanide, K 4 Fe(NC) 6, (yellow prussiate of potash), was first obtained by decomposing Prussian blue with caustic potash: Fe4[Fe(NC)6]3 + 12KHO = 3K 4 Fe(NC) 6 +4Fe(OH) 3; it may be also obtained by warming a solution of ferrous sulphate with an excess of potassium cyanide: FeS04-I-6KNC = K4Fe(NC)6+ K2S04.

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  • When fused with potassium carbonate it yields potassium cyanide; warmed with dilute sulphuric acid it yields hydrocyanic acid, but with concentrated sulphuric acid it yields carbon monoxide: 6H 2 O + K 4 Fe(NC) 6 + 6H 2 SO 4 = 2K 2 SO 4 + FeSO 4 + 3(NH4)2S04 + 6C0.

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  • The potassium salt may be prepared by adding potassium cyanide to ferrous sulphate solution, the brown precipitate so formed being then heated with potassium nitrite: 5 KNC + 2 FeSO 4 = 2 K 2 SO 4 + KFe2(NC)5, 2 KFe 2 (NC) 5 + 2 KNO 2 = 2 FeO + 2 K2Fe(NC)5 NO.

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  • They may be prepared by heating the alkyl iodides with potassium cyanide; by heating sulphuric acid esters with potassium cyanide; by distilling the acid-amides with phosphorus pentoxide; and by distilling amines (containing more than five atoms of carbon) with bromine and potash (A.

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  • In addition to these methods, the nitriles of the aromatic series may be prepared by distilling the aromatic acids with potassium sulphocyanide: C 6 H 5 CO 2 H -{- [[Kcns = Hcns -}- C6h5c02k, C 6 H 5 Co 2 H -}- Hcns = C 6 H 5 Cn]] -fH 2 S + C02; from the primary aromatic amines by converting them into diazonium salts, which are then decomposed by boiling with potassium cyanide and copper sulphate; by fusing the potassium salts of the sulphonic acids with potassium cyanide; by leading cyanogen gas into a boiling hydrocarbon in the presence of aluminium chloride (A.

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  • Allyl cyanide boils at 119° C. Benzonitrile boils at 190.6° C. When solidified it melts att7° C. It is easily soluble in alcohol and ether.

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  • Gautier (Ann., 1869, 151, p. 239) by the action of alkyl iodides on silver cyanide, and the distillation of the resulting compound with potassium cyanide in concentrated aqueous solution: RIR Ag(NC) 2 -)R NC+KAg(NC)2.

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  • The isonitriles dissolve silver cyanide readily, forming a soluble silver salt (cf.

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  • - Considerable discussion has taken place as to the structure of the metallic cyanides, since potassium cyanide and silver cyanide react with alkyl iodides to form nitriles and isonitriles respectively, thus apparently pointing to the fact that these two compounds possess the formulae KCN and AgNC. The metallic cyanides are analogous to the alkyl isocyanides, since they form soluble double silver salts, and the fact that ethyl ferrocyanide on distillation yields ethyl isocyanide also points to their isocyanide structure.

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  • Wade (loc. cit.) explains the formation of nitriles from potassium cyanide, and of isonitriles from silver cyanide by the assumption that unstable addition products are formed, the nature of which depends on the relative state of unsaturation of the carbon and nitrogen atoms under the varying conditions: KNC--KN :C(:C 2 H 5 I) --SKI +C2H5CN, AgNC->AgN(:C2H51)C---AgI-f-C2H5NC; that is, when the metal is highly electro-positive the carbon atom is the more unsaturated, the addition takes place on the carbon atom, and nitriles are produced.

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  • On the other hand, when there is but little electro-chemical difference between the radical of the cyanide and that of the reacting compound then the nitrogen atom is the more unsaturated element and.

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  • As an alternative test the cyanide may be decomposed by dilute hydrochloric acid, and the liberated hydrocyanic acid absorbed in a little yellow ammonium sulphide.

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  • Silver nitrate gives a white precipitate with cyanides, soluble in excess of potassium cyanide.

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  • Lengler, The Cyanide Industry, 1906 (Eng.

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  • Cyanogen compounds of chromium, analogous to those of iron, have been prepared; thus potassium chromocyanide, K 4 Cr(CN) 6.2H 2 0, is formed from potassium cyanide and chromous acetate; on exposure to air it is converted into the chromicyanide, K 3 Cr(CN) 6, which can also be prepared by adding chromic acetate solution to boiling potassium cyanide solution.

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  • Diazobenzenecyanide, C 6 H 5 N 2 CN, is an unstable oil, formed when potassium cyanide is added to a solution of a diazonium salt.

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  • Crotonic acid, so named from the fact that it was erroneously supposed to be a saponification product of croton oil, may be prepared by the oxidation of croton-aldehyde, CH3 CH:CH CHO, obtained by dehydrating aldol, or by treating acetylene successively with sulphuric acid and water; by boiling allyl cyanide with caustic potash; by the distillation of 0-oxybutyric acid; by heating paraldehyde with malonic acid and acetic acid to, oo C. (T.

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  • Cannizzaro); and on warming with alcoholic potassium cyanide it condenses to benzoin.

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  • It may also be prepared by heating a mixture of carbon, oxide of iron and magnesite to bright redness; and by heating a mixture of magnesium ferrocyanide and sodium carbonate, the double cyanide formed being then decomposed by heating it with metallic zinc. Electrolytic methods have entirely superseded the older methods.

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  • The remedy is to spray with kerosene emulsion or whale-oil soap; or if on cucumbers or tomatoes, it is best to fumigate with hydrocyanic acid gas, using one ounce of potassium cyanide to each woo cubic ft.

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  • a-Naphthoic acid, C 1 oH 7 CO 2 H, is formed by hydrolysis of the nitrile, obtained by distilling potassiuma-naphthalene sulphonate with potassium cyanide (V.

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  • In the case of iodine, the substitution is effected by adding a warm solution of potassium iodide to the diazonium solution, no copper or cuprous salt being necessary; whilst for the production of nitriles a solution of potassium cuprous cyanide is used.

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  • By diazotizing para-chloraniline and adding a cold solution of potassium cyanide, a salt (melting at 29° C.) is obtained, which readily loses nitrogen, and forms parachlorbenzonitrile on the addition of copper powder.

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  • Similar results have been obtained by using diazotized para-anisidine, a synand an anticompound being formed, as well as a third isomeric cyanide, obtained by evaporating para-methoxybenzenediazonium hydroxide in the presence of an excess of hydrocyanic acid at ordinary temperatures.

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  • p. 543), as has also aluminium turnings moistened with potassium cyanide and mercuric chloride, which decomposes water regularly at 70°, i gram giving 1.3 litres of gas (Mauricheau-Beaupre, Comptes rendus, 1908, 147, p. 310).

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  • Wdhler oxidized potassium ferrocyanide to potassium cyanate by fusing it with lead or manganese dioxide, converted this cyanate into ammonium cyanate by adding ammonium sulphate, and this on evaporation gives urea, thus: K 4 Fe(NC)r-->K CNO--->NH4CNO->CO (NH2)2 It may also be prepared by the action of ammonia on carbonyl chloride, diethyl carbonate, chlorcarbonic ester or urethane; by heating ammonium carbamate in a sealed tube to 130-140° C.; by oxidizing potassium cyanide in acid solution with potassium permanganate (E.

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  • Williamson): (CONH 2) 2 +HgO= CO(NH2)2+ Hg +CO 2 j by decomposing potassium cyanide with a dilute solution of sodium hypochlorite, followed by adding ammonium sulphate (A.

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  • It is of value in cyanide and opium poisoning and in the resuscitation of the apparently drowned.

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  • Potassium cyanide gives a greenish yellow precipitate of nickel cyanide, Ni(CN) 2, soluble in excess of potassium cyanide, forming a double salt, Ni(CN)2.2KCN, which remains unaltered when boiled with excess of potassium cyanide in presence of air (cf.

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  • Numerous methods have been devised for the separation of nickel and cobalt, the more important of which are: -the cobaltinitrite method by which the cobalt is precipitated in the presence of acetic acid by means of potassium nitrite (the alkaline earth metals must not be present); the cyanide method (J.

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  • Liebig, Ann., 1848, 6 5, p. 2 44; 1853, 87, p.128), in which the two metals are precipitated by excess of potassium cyanide in alkaline solution, bromine being afterwards added and the solution warmed, when the nickel is precipitated.

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  • The latter method has been modified by adding potassium cyanide in slight excess to the solution of the mixed salts, heating for some time and then adding mercuric oxide and water, the whole being then warmed on the water bath, when a precipitate of mercuric oxide and nickel hydroxide is obtained 666, 670).

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  • Succinonitrile, C2H4(CN)2r is obtained by the action of potassium cyanide on ethylene dibromide or by the electrolysis of a solution of potassium cyanacetate.

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  • The cyanide process, introduced about 1890, is now one of the most important factors in the utilization of low-grade and refractory gold and silver ores.

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  • The improved dioxide cyanide process was adopted about 1895.

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  • It may be detected by the addition of an aqueous solution of potassium cyanide, with which it gives a violet-red coloration, due to the formation of isopurpuric acid.

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  • It is decomposed by water with evolution of hydrogen, and on heating in a current of carbonic oxide forms barium cyanide (L.

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  • The potassium cyanide method is based on the fact that, when potassium cyanide is added to an ammoniacal solution of a salt of copper, the insoluble copper cyanide is formed, the end of the reaction being indicated by the disappearance of the blue colour of the solution.

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  • To the filtrate (or, if no silver is present, to the diluted nitric acid solution) io cc. of ammonia are added, and a standard solution of potassium cyanide is run in from a burette until the blue colour has nearly disappeared.

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  • The potassium cyanide solution is standardized by dissolving 0.5 gramme o£ pure copper in 5 cc. of nitric acid, diluting, adding io cc. of ammonia, and titrating exactly as described above.

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  • The ore is treated as described in the cyanide method until the copper precipitated by the aluminium foil has been washed and dissolved in 5 cc. of nitric acid; then 0.25 gramme of potassium chlorate is added, and the solution boiled nearly dry to oxidize any arsenic present to arsenic acid.

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  • Sodium chloride, characteristic of the Augustin process in which the ores, after a chloridizing roast, were extracted with brine, and the silver precipitated by copper, has almost wholly fallen into disuse; and potassium cyanide, which has become a very important solvent for finely divided gold, is rarely used in leaching silver ores.

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  • It readily dissolves in ammonia, the solution, on evaporation, yielding rhombic crystals of 2AgC1.3NH 3; it also dissolves in sodium thiosulphate and potassium cyanide solutions.

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  • It is formed in the hydrolysis of piperine by alcoholic potash, by the reduction of trimethylene cyanide (A.

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  • Nilson (Ber., 1874, 7, p. 1719) digests the well-washed chamber mud with a moderately concentrated solution of potassium cyanide, whereby the element goes into solution in the form of potassium selenocyanide, KSe(CN), from which it is precipitated by hydrochloric acid.

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  • Chem., 18 57, 71, p. 2 79) fuses the commercial selenium with potassium cyanide in a stream of hydrogen, takes up the melt in water and passes air through the solution; the precipitated tellurium is filtered off, and the solution then supersaturated with hydrochloric acid, when selenium is gradually deposited.

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  • It is also obtained when dry ammonia gas is passed into a dilute solution of selenyl chloride in benzene, the precipitate produced being digested with potassium cyanide to remove any selenium (V.

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  • It is a brickred powder which explodes when heated to 130° C. Selenium cyanide, Se(CN) 2, is obtained by decomposing silver selenocyanide with cyanogen iodide, or by the action of silver cyanide on a solution of selenium bromide in carbon bisulphide.

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  • A more complex cyanide, Se3(CN)2, is obtained by passing a current of chlorine and air into an aqueous solution of potassium selenocyanide (A.

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  • When heated to 180° C. in vacuo it yields the simple cyanide Se(CN) 2.

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  • Potassium selenocyanide, KSeCN, is obtained by the action of selenium on a concentrated aqueous solution of potassium cyanide, or by heating selenium with anhydrous potassium ferrocyanide (W.

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  • Meyer (Ber., 1902, 35, p. 1 59 1) by the electrolysis of silver selenite in the presence of potassium cyanide obtained the value 79.22.

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  • of Great Salt Lake) whose ores are reduced by the cyanide process.

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  • Cyanogen compounds also are present in the gas, and in large works, where the total quantity is sufficient, their extraction is effected for the production of either prussiate or cyanide of soda.

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  • Cyanogen compounds are extracted either direct from the gas, from the spent oxide or from ammoniacal liquor, and some large gas works now produce sodium cyanide, this being one of the latest developments in the gas chemical industry.

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  • Wiss., 1904, 34, p. 201), and also gold in commercial potassium cyanide solution (A.

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  • CO 2 H,with sodium amalgam, by conversion of trimethylene bromide into the cyanide and hydrolysis of this compound, or from acetoacetic ester, which, in the form of its sodium derivative, condenses with j3-iodopropionic ester to form acetoglutaric ester, CH 3 CO CH(CO 2 C 2 H 5) CH 2.

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  • Blood gases, like Hydrogen Cyanide, interfere with cell respiration.

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  • The group has told recent visitors to its enclave that it holds stocks of the deadly chemical agents ricin, cyanide gas and aflatoxin.

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  • Virtual Photographer: Optik Verve Labs' Virtual Photographer provides professional-looking photo filters such as radiance, dreamy, high key, cyanide, brownie, and glamour.

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  • Cancer causing chemicals like cyanide, propargite and dicofol have been used in conventional farming, contaminating local wildlife, water and soil.

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  • At one time or another, a number of chemical agents used in conventional farming have been linked to cancer in humans, like dicofol, cyanide and propargite.

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  • Cyanide interferes with respiration at the cellular level.

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  • Apricots, cherries, peaches, and apples all produce healthful fruit, but their seeds contain a form of cyanide that can kill a child if chewed in sufficient quantities.

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  • One hundred milligrams (mg) of moist, crushed apricot seeds can produce 217 mg of cyanide.

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  • He or she may also check for smoke inhalation, carbon monoxide poisoning, cyanide poisoning, other event-related trauma, or, if suspected, evidence of child abuse.

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  • In institutions where it is available, hyperbaric oxygen therapy may be used to treat smoke inhalation, resulting in severe carbon monoxide or cyanide poisoning.

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  • It may be prepared by boiling a-dichlorpropionic acid with silver oxide; by the hydrolysis of acetyl cyanide with hydrochloric acid (J.

    0
    1
  • CN, may be prepared by the action of silver cyanide on acetyl chloride; or of acetyl chloride on nitrosoacetone (L.

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    1
  • The yield reached its lowest point in 1899, but subsequently increased through the application of improved machinery, while the tailings of the old diggings were treated by the cyanide process with profitable results.

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    1
  • Potassium cyanide reacts with this acid to form the corresponding dinitrile, which is converted by hydrochloric acid into citric acid.

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    1
  • Held synthesized the acid from ethyl chlor-acetoacetate (from chlorine and acetoacetic ester) by heating with potassium cyanide and saponifying the resulting nitrile.

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    1
  • The same methyl iodide gave with potassium cyanide, acetonitril, which was hydrolysed to acetic acid; this must be C(Coch) a H b H c H d.

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    1
  • Filter from the bismuth hydrate, and if copper is present, add potassium cyanide till the colour is destroyed, then pass sulphuretted hydrogen, and cadmium is precipitated as the yellow sulphide.

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    1
  • In the first group, we have to notice the titration of a cyanide with silver nitrate, when a milkiness shows how far the reaction has gone; the titration of iron with permanganate, when the faint pink colour shows that all the iron is oxidized.

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  • A blue coloration indicates nitrogen, and is due to the formation of potassium (or sodium) cyanide during the fusion, and subsequent interaction with the iron salts.

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  • 43) has found that solutions of diphenylamine in methyl cyanide possess an excess of pressure-producing particles and yet are non-conductors of electricity.

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  • Again, Hittorf has shown that the effect of a cyanide round a copper electrode is to combine with the copper ions.

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  • When heated with alcoholic potassium cyanide they are converted into benzoins.

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  • Thiele, Ann., 1898, 302, p. 299): HN:CC NH NH2 OC C 6 H 5 NH N + -> HN:CC C C6 H 5 NH 2 OC C6H5 N = C/-C6H5 Wolff has obtained a chloro-derivative by the action of potassium cyanide on diazoacetophenone and subsequent treatment with acid.

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  • Tin compounds when heated on charcoal with sodium carbonate or potassium cyanide in the reducing blowpipe flame yield the metal and a scanty ring of white Sn02.

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  • Further work on cyanogen and connected substances yielded a great number of interesting derivatives, and he described an improved method for the manufacture of potassium cyanide, an agent which has since proved of enormous value in metallurgy and the arts.

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  • This view had currency until 1849, when Wohler showed that the crystals are a compound, Ti(CN)2.3T13N2, of a cyanide and a nitride of the metal.

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  • Titanic oxides when fused on charcoal, even with potassium cyanide, yield no metal.

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  • CYANIDE, in chemistry, a salt of prussic or hydrocyanic acid, the name being more usually restricted to inorganic salts, i.e.

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  • An important nucleus-synthetic reaction is the saponification of nitriles, which may be obtained by the interaction of potassium cyanide with a halogen substitution derivative or a sulphonic acid.

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  • Aurous cyanide, AuCN, forms yellow, microscopic, hexagonal tables, insoluble in water, and is obtained by the addition of hydrochloric acid to a solution of potassium aurocyanide, KAu(CN)2.

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  • - This process depends upon the solubility of gold in a dilute solution of potassium cyanide in the presence of air (or some other oxidizing agent), and the subsequent precipitation of the gold by metallic zinc or by.

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  • The solubility of gold in cyanide solutions was known to K.

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  • The action proceeds in two stages; in the first hydrogen peroxide and potassium aurocyanide are formed, and in the second the hydrogen peroxide oxidizes a further quantity of gold and potassium cyanide to aurocyanide, thus (1) 2Au+4KCN +02+2H20=2KAu(CN)2+4KOH+H202;(2)2Au+4KCN+2H202= 2KAu(CN) 2 +4KOH.

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  • In the Transvaal the operation occupies 32 to 4 days for fine sands, and up to 14 days for coarse sands; the quantity of cyanide per ton of tailings varies from 0.26 to 0.28 lb, for electrolytic precipitation, and o 5 lb for zinc precipitation.

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  • According to Christy, the precipitation with zinc follows equations for 2 according as potassium cyanide is present or not: (1) 4 KAu(CN)2+4Zn+2H20=2Zn(CN)2+ K 2 Zn(CN) 4 +Zn(OK) 2 +4H+4Au; (2) 2KAu (CN) 2 +3Zn+4KCN+2H 2 0 = 2K 2 Zn(CN) 4 +Zn(OK) 2 +4H+2Au; one part of zinc precipitating 3.1 parts of gold in the first case, and 2.06 in the second.

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  • It may be noticed that the potassium zinc cyanide is useless in gold extraction, for it neither dissolves gold nor can potassium cyanide be regenerated from it.

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  • - The electrolytic separation of the gold from cyanide solutions was first practised in the Transvaal.

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  • In the process employed at the Worcester Works in the Transvaal, the liquors, containing about 150 grains of gold per ton and from 0.08 to o 01% of cyanide, are treated in rectangular vats in which is placed a series of iron and leaden plates at intervals of 1 in.

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  • A cyanide bath, as used in electroplating, would dissolve the gold, but is not suitable for refining, because other metals (silver, copper, &c.) passing with gold into the solution would deposit with it.

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  • The same methyl iodide gave with potassium cyanide, acetonitril, which was hydrolysed to acetic acid; this must be C(Coch) a H b H c H d.

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  • Again, Hittorf has shown that the effect of a cyanide round a copper electrode is to combine with the copper ions.

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  • An important nucleus-synthetic reaction is the saponification of nitriles, which may be obtained by the interaction of potassium cyanide with a halogen substitution derivative or a sulphonic acid.

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  • Potash solution converts it into a mixture of potassium cyanide and cyanate.

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  • p. 299), or by the addition of a concentrated solution of potassium cyanide to one of copper sulphate, the mixed solutions being then heated.

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  • When cyanogen is prepared by heating mercuric cyanide, a residue known as para-cyanogen, (CN)x, is left; this is to be regarded as a polymer of cyanogen.

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  • Here the ions are potassium and the group Ag(CN)2.1 Each potassium ion as it reaches the cathode precipitates silver by reacting with the solution in accordance with the chemical equation K--+KAg(CN) 2 =2KCN+Ag, while the anion Ag(CN) 2 dissolves an atom of silver from the anode, and re-forms the complex cyanide KAg(CN) 2 by combining with the 2KCN produced in the reaction described in the equation.

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  • Zinc is commonly deposited by electrolysis on iron or steel goods which would ordinarily be "galvanized," but which for any reason may not conveniently be treated by the method of immersion in fused zinc. The zinc cyanide bath may be used for small objects, but for heavy goods the sulphate bath is employed.

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  • The concentration of the simple copper ions is then so much diminished that the copper plate becomes an anode with regard to zinc. Thus the cell - copper I potassium cyanide solution I potassium sulphate solution - zinc sulphate solution I zinc - gives a current which carries copper into solution and deposits zinc. In a similar way silver could be made to act as anode with respect to cadmium.

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  • Potassium ruthenium cyanide, K4Ru(CN) 6.3H 2 O, formed when potassium ruthenate is boiled with a solution of potassium cyanide, crystallizes in colourless plates which are soluble in water.

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