Potassium compounds cyanide

Cyanide is usually found in compounds (substances formed by joining two or more chemicals). Cyanide can interact with metals and other organic compounds (compounds that include carbon). Sodium cyanide and potassium cyanide are examples of simple cyanide compounds. Cyanide can be produced by certain bacteria, fungi, and algae, and is found in a number of foods and plants. In your body, cyanide can combine with a chemical (hydroxocobalamin) to form vitamin B12 (cyanocobalamin). In certain plant foods, including almonds, millet sprouts, lima beans, soy,... 

Oral exposure to cyanide usually results from accidental, homicidal, or suicidal ingestion of cyanide salts. Sodium cyanide and potassium cyanide are the most frequently studied cyanide compounds. Copper cyanide, potassium silver cyanide, silver cyanide, and calcium cyanide are other compounds that humans could encounter through oral or dermal exposure. Cassava roots and certain fruit pits contain compounds that can be broken down to form cyanide. Cassava roots form the staple diet of some populations in Africa, Central and South America, and Asia. However, it must be noted that cassava roots are notoriously deficient in protein and other nutrients and contain many other compounds, in addition to cyanide, that could be responsible for some of the observed toxic effects. Thiocyanate is a metabolite of cyanide that is formed in the body after exposure to cyanide compounds. When possible, all oral exposures are expressed as mg CN/kg/day. 

Export volumes of cyanide compounds (foreign and domestic volumes combined) shown in Table 4-2 fluctuated widely over the period January 1989 and April 1994. No obvious trends were evident except for potassium cyanide, where export volumes decreased from 3.13 million pounds in 1989 to 0.46 million pounds in 1994. Export data could not be found in the available literature for calcium cyanide, potassium silver cyanide, cyanogen, or cyanogen chloride. 

The so-called acyloin or benzoin condensation is a further interesting aldehyde reaction. In the aromatic series it takes place as a result of the action of potassium cyanide, and it is very probable that the potassium compound of the cyanohydrin is formed as an intermediate pro-... 

The double compound, [Cr(NH3)6H20][Cr(CN)8], is precipitated from the aquo-pentammino-chloride on addition of potassium chromi-cyanide it separates as a sparingly soluble yellow crystalline powder, and on heating with concentrated hydrochloric acid decomposes with formation of ehloro-pentammino-chloride. The ferricyanide, [Cr(NH3)B H20][Fe(CN)6], is precipitated from a dilute solution of the aquo-pentammino-ehloride on addition of potassium ferricyanide, and crystallises in vellowish-brown prisms. The cobalti-cyanide, [Cr(NH3)5H20] [Co(CN)6], obtained, by the addition of potassium cobalti-cyanide, in yellowish-brown crystals, is isomeric with the chromi-eyanide of aquo-pentammino-cobalt, [Co(NH3)sH20][Cr(CN)6]. 

Edmond Becquerel (1820-1891) was the nineteenth-century scientist who studied the phosphorescence phenomenon most intensely. Continuing Stokes s research, he determined the excitation and emission spectra of diverse phosphors, determined the influence of temperature and other parameters, and measured the time between excitation and emission of phosphorescence and the duration time of this same phenomenon. For this purpose he constructed in 1858 the first phosphoroscope, with which he was capable of measuring lifetimes as short as 10-4 s. It was known that lifetimes considerably varied from one compound to the other, and he demonstrated in this sense that the phosphorescence of Iceland spar stayed visible for some seconds after irradiation, while that of the potassium platinum cyanide ended after 3.10 4 s. In 1861 Becquerel established an exponential law for the decay of phosphorescence, and postulated two different types of decay kinetics, i.e., exponential and hyperbolic, attributing them to monomolecular or bimolecular decay mechanisms. Becquerel criticized the use of the term fluorescence, a term introduced by Stokes, instead of employing the term phosphorescence, already assigned for this use [17, 19, 20], His son, Henri Becquerel (1852-1908), is assigned a special position in history because of his accidental discovery of radioactivity in 1896, when studying the luminescence of some uranium salts [17]. 

Prussian Blue is probably the most famous blue pigment. It was discovered by accident in 1704 and is made from potassium ferro-cyanide and ferric chloride. Heinrich Diesbach, a colour manufacturer of Berlin, had run out of potash (potassium carbonate) with which to make a red lake so he borrowed some from Johann Dippel an alchemist. While this worked fine, something happened to the solution after he had filtered off the red lake it turned a deep blue colour. Dip-pel s potash had been made from calcined bones and these contained cyanide from the decomposition of their protein component and the cyanide had reacted to a deep blue compound which we now know as... 

The specific activity of 357 was 2.09 GBq mmol-1 and the radiochemical purity >97%. The overall radiochemical yield from potassium [14C]cyanide was 16% (150.5 MBq). The NMR spectra of intermediate compounds indicated that the reactions of equation 152 yielding 357 proceeded with complete retention of configuration at the chiral centre at C(8). In the reaction of RC1 with Na14CN, the S 2 displacement occurred with an overall retention of configuration due to participation of the nitrogen ring336,338. 

In qualitative analysis copper is detected by precipitation as cupric sulphide from hydrochloric-acid solutions of its salts. To prevent the formation of a colloidal precipitate, the solution should be hot, and should contain excess of the acid. The sulphide is soluble in hot, dilute nitric acid, and in potassium-cyanide solution, but almost insoluble in solutions of alkali-metal sulphides. It dissolves to some extent in ammonium-sulphide solution. Other aids in the detection of copper are the blue colour of solutions of cupric-ammonia salts the reddish-brown precipitate of cupric ferrocyanide, produced by addition of potassium ferro-cyanide to cupric solutions the formation of an intense purple coloration by the interaction of hydrogen bromide and cupric salts, a very delicate reaction2 the formation of a bluish-green borax bead and the ready isolation of the metal from its compounds by the action of reducers. 

Cobaltic ion is unstable, and an attempt to oxidize cobaltous ion usually leads to the precipitation of cobaltic hydroxide, Co(OH)3. The covalent cobaltic compounds are very stable. The most important ot these are potassium cobaltinitrite, KgCo(N02)6> and potassium cobalti-cyanide, K3Co(CN). ... 

Chemical properties of iron. Passivity. Ferrous compounds ferrous sulfate, ferrous ammonium sulfate, ferrous chloride, ferrous hydroxide, ferrous sulfide, ferrous carbonate. Ferric compounds ferric nitrate, ferric, sulfate, iron alum, ferric chloride, ferric hydroxide, ferric oxide (rouge, Venetian red). Potassium ferro-cyanide, potassium ferricyanide, Prussian blue. 

The iron salts of ferro and ferricyanic acid are the compounds to which the names cyanogen and cyanide are due. Two of these salts are of deep blue color and the Greek word from which cyanogen and cyanide are derived is cyanos which means blue. The ferric ferro-cyanide, Fe4 "(Fe"(CN6)3, is known as Prussian blue and the ferrous ferri-cyanide, Fe3"(Fe" (CN)6)2, is Turnbull s blue. These compounds are formed when ferric salts in solution are treated with potassium ferro-cyanide and when ferrous salts in solution are treated with potassium ferricyanide. They are common qualitative tests for the two forms of iron salts. The compounds are also used as laundry blueing and are formed in the blue print process of photography. 

Potassium ferro-cyanide so prepared is the starting point for the preparation of the other cyanogen compounds.. When distilled with diluie sulphuric acid, hydrogen cyanide is evolved. 

The bromide is prepared in the same way as the chloride, is insoluble in organic solvents, and melts at 251 C, It reacts "with alkaline sodium stannite solution, yielding a brick-red compound I., which turns brown on exposure to iightl This decomposition product when extracted with hot benzene gives II., the corresponding mercuric compound to I. It melts at 190° C., is insoluble in water, alkalies, dilute acids, or acetone, readily soluble in benzene or toluene, and is decomposed by concentrated liydrochloric acid. With mercuric chloride or picric acid it gives precipitates, but remains unchanged when boiled with potassium hydroxide, cyanide, or iodide. 

Applications Potassium hydroxide is utilized in the manufacture of other potassium compounds (potassium carbonate, potassium phosphates e.g. tetrapotassium pyrophosphate, potassium permanganate, potassium bromate, potassium iodate, potassium cyanide etc.), of dyes, special soaps and battery liquids. It is also used in photographic developers, in glass manufacture and as a drying and absorption agent. In many of these applications its use is declining. 

The possibility that homoerythrina alkaloids exist has been anticipated from biosynthetic consideration. Homoerythrinadienones 110 and 111 were synthesized by phenol oxidation with potassium ferri-cyanide 48) of secondary amines 108 and 109, a homolog of erythrina dienone. This compound 110 is believed to be involved in the biogenesis of the homoerythrina alkaloids. 

Propionic acid—C,H,CO,OH —74—is formed in many decompositions of organic substances By the action of caustic potassa ui>ou sugar, starch, gum. and ethyl cyanide during fermentation, vinous or acetic in the distillation of wood during the putrefaction of peas, beans, etc. by the axidation of normal propylic alcohol, etc. It is best prepared by heating elliyl cyanide with potash until the odor of the ether has disappeared the acid is then liberated from its potassium compound by H.SO, and purified. 

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