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Of organic acids

In the former, it gives precipitates with halides (except the fluoride), cyanides, thiocyanates, chromates(VI), phosphate(V), and most ions of organic acids. The silver salts of organic acids are obtained as white precipitates on adding silver nitrate to a neutral solution of the acid. These silver salts on ignition leave silver. When this reaction is carried out quantitatively, it provides a means of determining the basicity of the acid... [Pg.430]

S-Benzyl-wo-thiuronium chloride (S-benzyl-iao-thiourea hydrochloride) reacts with the alkali metal salts of organic acids to produce crystalline S benzyl-MO-thiuronium salts ... [Pg.363]

It is frequently advisable in the routine examination of an ester, and before any derivatives are considered, to determine the saponification equivalent of the ester. In order to ensure that complete hydrolysis takes place in a comparatively short time, the quantitative saponi fication is conducted with a standardised alcoholic solution of caustic alkali—preferably potassium hydroxide since the potassium salts of organic acids are usuaUy more soluble than the sodium salts. A knowledge of the b.p. and the saponification equivalent of the unknown ester would provide the basis for a fairly accurate approximation of the size of the ester molecule. It must, however, be borne in mind that certain structures may effect the values of the equivalent thus aliphatic halo genated esters may consume alkali because of hydrolysis of part of the halogen during the determination, nitro esters may be reduced by the alkaline hydrolysis medium, etc. [Pg.392]

Reaction with alcoholic silver nitrate. To carry out the test, treat 2 ml. of a 2 per cent, solution of silver nitrate in alcohol with 1 or 2 drops (or 0 05 g.) of the compound. If no appreciable precipitate appears at the laboratory temperature, heat on a boiling water bath for several minutes. Some organic acids give insoluble silver salts, hence it is advisable to add 1 drop of dilute (5 per cent.) nitric acid at the conclusion of the test most silver salts of organic acids are soluble in nitric acid. [Pg.1059]

Polonium is readily dissolved in dilute acids, but is only slightly soluble in alkali. Polonium slats of organic acids char rapidly halide amines are reduced to the metal. [Pg.148]

TABLE 5.2 Solubilities of Inorganic Compounds and Metal Salts of Organic Acids in Water at Various Temperatures... [Pg.368]

Dowex 1-X4 1.0 0.70 Strongly basic anion exchanger with S-DVB matrix for separation of organic acids, nucleotides, phosphoinositides, and other anions. Molecular weight exclusion is <1400. [Pg.1110]

Processes rendered obsolete by the propylene ammoxidation process (51) include the ethylene cyanohydrin process (52—54) practiced commercially by American Cyanamid and Union Carbide in the United States and by I. G. Farben in Germany. The process involved the production of ethylene cyanohydrin by the base-cataly2ed addition of HCN to ethylene oxide in the liquid phase at about 60°C. A typical base catalyst used in this step was diethylamine. This was followed by liquid-phase or vapor-phase dehydration of the cyanohydrin. The Hquid-phase dehydration was performed at about 200°C using alkah metal or alkaline earth metal salts of organic acids, primarily formates and magnesium carbonate. Vapor-phase dehydration was accomphshed over alumina at about 250°C. [Pg.183]

Vapors emitted from the materials of closed storage and exhibit cases have been a frequent source of pollution problems. Oak wood, which in the past was often used for the constmction of such cases, emits a significant amount of organic acid vapors, including formic and acetic acids, which have caused corrosion of metal objects, as well as shell and mineral specimens in natural history collections. Plywood and particle board, especially those with a urea—formaldehyde adhesive, similarly often emit appreciable amounts of corrosive vapors. Sealing of these materials has proven to be not sufficiently rehable to prevent the problem, and generally thek use for these purposes is not considered acceptable practice. [Pg.429]

A report on the continuous flash pyrolysis of biomass at atmospheric pressure to produce Hquids iadicates that pyrolysis temperatures must be optimized to maximize Hquid yields (36). It has been found that a sharp maximum ia the Hquid yields vs temperature curves exist and that the yields drop off sharply on both sides of this maximum. Pure ceUulose has been found to have an optimum temperature for Hquids at 500°C, while the wheat straw and wood species tested have optimum temperatures at 600°C and 500°C, respectively. Organic Hquid yields were of the order of 65 wt % of the dry biomass fed, but contained relatively large quantities of organic acids. [Pg.23]

Detergents are metal salts of organic acids used primarily in crankcase lubricants. Alkylbenzenesulfonic acids, alkylphenols, sulfur- and methjiene-coupled alkyl phenols, carboxyUc acids, and alkylphosphonic acids are commonly used as their calcium, sodium, and magnesium salts. Calcium sulfonates, overbased with excess calcium hydroxide or calcium carbonate to neutralize acidic combustion and oxidation products, constitute 65% of the total detergent market. These are followed by calcium phenates at 31% (22). [Pg.242]

Other simple nickel salts of organic acids include the oxalate [20543-06-0] oleate [68538-38-5], and stearate [2223-95-2]. The latter two have been used as oil-soluble nickel forms in the dyeing of synthetic polyolefin fibers (see Driers and metallic soaps). Nickel oxalate has been used as a catalyst intermediate (59). [Pg.13]

A variety of shale-protective muds are available which contain high levels of potassium ions (10). The reaction of potassium ions with clay, well known to soil scientists, results in potassium fixation and formation of a less water-sensitive clay. Potassium chloride, potassium hydroxide, potassium carbonate [584-08-7] (99), tetrapotassium pyrophosphate [7320-34-5] (100), and possibly the potassium salts of organic acids, such as potassium acetate [127-08-2] (101) and formate, have all been used as the potassium source. Potassium chloride is generally preferred because of its low cost and availabihty. [Pg.182]

Whereas metal salts of carboxyUc acids cataly2e the above reactions, these are not sufftciendy basic to cleave Si—H bonds. Mercury salts of organic acids in the presence of silver perchlorate, however, do react to produce organoacyloxysdanes (111). [Pg.27]

Alkaline Degradation. At high pH, sucrose is relatively stable however, prolonged exposure to strong alkaU and heat converts sucrose to a mixture of organic acids (mainly lactate), ketones, and cycHc condensation products. The mechanism of alkaline degradation is uncertain however, initial formation of glucose and fructose apparendy does not occur (31). In aqueous solutions, sucrose is most stable at —pH 9.0. [Pg.5]

The decomposition of dithionite in aqueous solution is accelerated by thiosulfate, polysulfide, and acids. The addition of mineral acid to a dithionite solution produces first a red color which turns yellow on standing subsequentiy, sulfur precipitates and evolution of sulfur dioxide takes place (346). Sodium dithionite is stabilized by sodium polyphosphate, sodium carbonate, and sodium salts of organic acids (347). [Pg.150]

Plastics and Synthetic Products. To prevent degradation of plastics at elevated processing temperatures, it is necessary to use suitable heat stabilizers. Eor example, flexible poly(vinyl chloride) (PVC) manifests uncontroUed color development in the absence of stabilizers. Accordingly, cadmium salts of organic acids are typically used in a synergistic combination with corresponding barium salts, in about a 1 3 cadmium barium ratio, to provide a cost-competitive heat stabilizer for flexible PVC. [Pg.388]

Salts of Organic Acids. Calcium salts of organic acids may be prepared by reaction of the carbonate hydroxide and the organic acid (9). Calcium lactate [814-80-2] is an iatermediate ia the purification of lactic acid from fermentation of molasses. Calcium soaps, soaps of fatty acids, ate soluble ia hydrocarbons, and are useful as waterproofing agents and constituents of greases (9). [Pg.408]


See other pages where Of organic acids is mentioned: [Pg.94]    [Pg.363]    [Pg.1038]    [Pg.37]    [Pg.180]    [Pg.437]    [Pg.164]    [Pg.503]    [Pg.266]    [Pg.512]    [Pg.509]    [Pg.379]    [Pg.457]    [Pg.30]    [Pg.238]    [Pg.95]    [Pg.293]    [Pg.160]    [Pg.390]    [Pg.368]    [Pg.75]    [Pg.292]    [Pg.397]   
See also in sourсe #XX -- [ Pg.305 ]




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Acid-Base Equilibria of Organic Radicals

Acid-base properties, of organic

Acid-base properties, of organic substances

Acids, nomenclature of isopoly and organic, basic beryllium derivatives

Activity of organic acids

Addition of Organic Acids to Propene

Analysis of organic acids

Analysis of organic acids using gas chromatography

Application of organic acids

Application of organic acids in food preservation

Basic Beryllium Derivatives of Organic Acids

Beryllium complex compounds basic, of organic acids

Byproduct Gypsum from the Manufacture and Purification of Organic Acids

Cellulose Esters of organic acids

Cellulose esters of, with organic acids

Classes of Organic Acids

Concentrations of organic acids

Concentrations of organic acids in blood

Concentrations of organic acids in urine

Constants of Organic Acids and Bases

Decarboxylation, of organic acids

Derivatives of Organic Acids

Determination of 1 to 90 Organic Nitrogen in Polymers Kjeldahl Digestion - Boric Acid Titration Method

Determination of organic acids which are volatile with steam

Disorders of organic acid metabolism

Dissociation Constants of Organic Acids and

Dissociation Constants of Organic Acids and Bases

Dissociation constants of organic acids

Electronically excited states of organic molecules, acid-base properties

Esters of Organic Acids

Esters of, with organic acids

Extraction of organic acids

First Dissociation Constants of Organic Acids in Aqueous Solution at

Fordyce, Charles R., Cellulose Esters of Organic Acids

Fractionation of organic acids

Functional Organization of Fatty Acid Synthase

Halogenated Esters of Organic Acids

Hydrazine salts of organic acids

Hydrolytic reactions of organic acid derivatives

Involving Fractionation of the Organic Acids

Ionization of organic acids

Mass spectra of organic acids and their derivatives

Metal hydrazines of organic acids

More than a century of preservation with organic acids

Nature and composition of organic acids

Number of undissociated organic acids that enter the bacterial cell

Of organic acids and bases

Organic Acids in the Study of Metabolic Diseases

Organic acids, separation of

Organization of Ferrocenoyl Amino Acids

Partition of a Carboxylic Acid between the Aqueous and Organic Phases

Physiological actions of organic acids

Production of organic acids

Protective effects of organic acids

Quantitative analysis of organic acids after separation by column chromatography

R. Fordyce, Cellulose Esters of Organic Acids

Reactions of Superoxide Ion with Organic H Acids

Role of organic acids in tolerance

Salts of organic acids

Separation of Organic Acids on Dowex Resins

Solubility and Acid-Base Properties of Organic Substances

Solubility of organic acids

Solutions of nitric acid in organic solvents

Susceptibility of and resistance to organic acids

The state of nitric acid in inert organic solvents

Uptake of Other Monomers and LMW Compounds Organic Acids

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