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Cupric ferricyanide

Potassium cupric ferricyanide [potassium copper(II)hexakis (cyanoferrate(3-))] KCuii[Fe(CN)6] [53295-15-1]... [Pg.422]

White silver cyanide, thiocyanate, ferro- and yellow ferricyanide are decomposed with production of ignition-resistant silver. All metal ferro- and ferricyanides of the base metals leave a residue of ferric oxide and the particular metal oxide. For instance, the colorless ferrocyanides of zinc, cadmium, magnesium, calcium, barium, strontium, thorium etc. become yellow-brown Prussian blue and Turnbull s blue become dark (Fe304) and, later, brown (FegOg). Cupric ferricyanide (brown) and cupric ferrocyanide (violet-brown) are blackened when ignited because of the formation of cupric oxide. [Pg.73]

Ammoniacal cupric ferricyanide Potassium copper pyrophosphate and p-dimethylaminobenzylidene- 0.2 346... [Pg.626]

Decolorization of blue starch-iodine Cupric ferricyanide 351 351... [Pg.638]

The most suitable oxidizing agent is potassium ferricyanide, but ferric chloride, hydrogen peroxide ia the presence of ferrous salts, ammonium persulfate, lead dioxide, lead tetraacetate or chromate, or silver and cupric salts may be useful. Water mixed, eg, with methanol, dimethylformamide, or glycol ethers, is employed as reaction medium. [Pg.430]

Chemical complexes of various transition metals have been shown to promote N-nitrosation (28). These metal complexes include ferrocyanide, ferricyanide, cupric ion, molybate ion, cobalt species, and mercuric acetate. All of the reactions are thought to proceed by oxidation-reduction mechanisms. However, such promotion may not be characteristic of transition metal complexes in general, since ferricyanide ion has been shown to promote nitrosation in metalworking fluids, whereas ferric EDTA does not (2 0). Since the metalworking operation generates metal chips and fines which build up in the fluids, this reaction could be of significance in the promotion of nitrosamine formation in water-based metalworking fluids. [Pg.162]

Oxidation of JV-hydroxypiperidine with cupric acetate or potassium ferricyanide gives J1-piperideine 1-oxide (30) in addition to a dimer or trimer.184,185 Dehydrogenation of l-hydroxy-2-phenylpiperidine takes a similar course.189... [Pg.180]

Since L-sorbose is a reducing sugar a number of methods for its determination, based on this property, have been reported. Titration with the ceric sulfate, potassium ferricyanide reagent showed a fructose to sorbose ratio of 1.1,86 Cupric citrate87 as well as cupric tartrate87 reagents appear to be equally useful. [Pg.117]

Occluded hydrogen is more reactive chemically than the normal gas. Hydrogenated palladium precipitates mercury and mercurous chloride from an aqueous solution of the dichloride, without any evolution of hydrogen. It reduces ferric salts to ferrous potassium ferricyanide to ferrocyanide chlorine water to hydrochloric add iodine water to hydriodic acid 2 chromates to chromic salts ceric to cerous salts whilst cupric, stannic, arsenic, manganic, vanadic, and molybdic compounds are also partially reduced.3... [Pg.181]

When potassium ferricyanide is warmed with a solution of bleaching powder to 70° C. a considerable evolution of gas takes place, and a reddish deposit of ferric oxide and calcium carbonate is formed. The filtered solution is concentrated and the potassium nitroprusside extracted with alcohol, and converted into the insoluble copper salt by addition of cupric chloride. This latter is decomposed with sodium hydroxide, yielding the sodium salt, which may be further purified by dissolving in a little water, addition of alcohol, and subsequent evaporation after filtering off any insoluble material.2 The constitution to be assigned to sodium nitroprusside in particular, and hence to nitro-prussides in general, has been a subject of debate, Browning s3 formula is —... [Pg.229]

The nature of the active site in beta-amylase is not unambiguously known for enzymes from different sources. Early experiments on purified barley and on malted barley first indicated, from studies of the modification of the enzyme with nitrous acid and ketene, that free tyrosine and sulfhydryl groups are essential for activity, whereas free a-amino groups are not. The importance of the sulfhydryl groups was emphasized by the partial recovery of activity of the modified or oxidized enzyme (that is, treated with nitrous acid, iodine, phenyl mercuribenzoate, ferricyanide, and cupric ions) when it was treated with hydrogen sulfide or cysteine. Barley feeto-amylase (not highly purified) has been reported to contain 12—15 sulfhydryl groups per molecule by titration with p-chloromercuribenzoate, and the loss of free sulfhydryl content by treatment with L-ascorbic acid in the presence of cupric ions was found to be directly related to the loss of activity. [Pg.334]

As already oudined, inhibition is essentially complete when caused by reagents that react with sulfhydryl groups (for example, p-chloro-mercuribenzoate, p-mercuribenzoate, o-iodosobenzoate, L-ascorbic acid silver, cupric, and mercuric ions iodine, and ferricyanide) this inactivation can be reversed to some extent by hydrogen sulfide and by cysteine. Lineweaver—Burk graphs have shown that the action of L-ascorbic acid is noncompetitive, and L-ascorbic acid acting in the presence of cupric ions probably causes formation of an inactive cuprous-enzyme. The action of p-chloromercuribenzoate on barley beta-amylase has been shown to be a competitive inhibition. In contrast, the soya-bean p-chloromercuribenzoate inhibition is noncompetitive, and the extent of inhibition is inversely related to the concentration of acetate ion. The latter exhibits a protective effect, and there... [Pg.336]

Diimide, HN=NH. The reagent, generated in situ by cupric ion-catalyzed oxidation of hydrazine with oxygen (air), hydrogen peroxide, potassium ferricyanide, or mercuric oxide, reduces olefins, alkynes, and azo compounds. Reduction of the... [Pg.862]

Some complex ions are so stable that one or more of the groups from which they are formed do not exist in appreciable amounts outside the complex. In such a case the formula for the entire complex is written. Thus, the ferricyanide ion is always written as [Fe(CN)5], never as separate ferric and cyanide ions. [Cu(NH3>4] is the notation for the comon blue complex ion formed by cupric salts in ammonia solutions. [Pg.177]

OXIDATIVE COUPLING Cupric acetate. Potassium ferricyanide. Silver oxide. Thallium-(111) trifluoroacetate. Vanadium oxytrifluoride. [Pg.782]

An inorganic molecule that contains several atoms, including one or more metal atoms, is called an inorganic complex or coordination compound. An example is nickel tetracarbonyl, Ni(CO)4. An inorganic complex with an electric charge is called a complex ion. Familiar examples of complex ions are the ferrocyanide ion, Fe(CN)e - the ferricyanide ion, Fe(CN)e the hydrated aluminum ion, A1(H20)6, and the deep blue cupric ammonia complex ion, Cu(NH3)4 +, which is formed by adding ammonium hydroxide to a solution of cupric salt. Complex ions are important in the methods of separation used in qualitative and quantitative chemical analysis and in various industrial processes. [Pg.541]

Spot tests for hydrazine can be based on this reaction if carried out in the presence of anions which form cuprous salts that are insoluble in ammonia. Ferricyanide and ferrocyanide ions, whose cupric salts are easily soluble in ammonia, are suitable. [Pg.339]

Consequently, a suspension of copper sulfide is completely clarified by cyanides. This fact may be used to detect cyanides even in the presence of ferrocyanides, ferricyanides, iodides, bromides, chlorides, and thiocyanates. The test may be made on paper impregnated with cupric sulfide the sensitivity is greater. [Pg.348]


See other pages where Cupric ferricyanide is mentioned: [Pg.351]    [Pg.626]    [Pg.351]    [Pg.626]    [Pg.277]    [Pg.220]    [Pg.596]    [Pg.361]    [Pg.353]    [Pg.562]    [Pg.754]    [Pg.1390]    [Pg.139]    [Pg.515]    [Pg.220]    [Pg.105]    [Pg.106]    [Pg.441]    [Pg.217]    [Pg.651]    [Pg.440]    [Pg.6]    [Pg.342]    [Pg.62]   
See also in sourсe #XX -- [ Pg.221 ]

See also in sourсe #XX -- [ Pg.2 , Pg.3 , Pg.4 , Pg.5 , Pg.6 , Pg.7 , Pg.8 , Pg.9 , Pg.10 , Pg.11 , Pg.12 ]

See also in sourсe #XX -- [ Pg.339 , Pg.346 , Pg.351 ]




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Cupric

Ferricyanide

Potassium cupric ferricyanide

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