Catalytic decomposition of acetonedicarboxylic acid

1968 ◽  
Vol 46 (6) ◽  
pp. 823-832 ◽  
Author(s):  
D. W. Larson ◽  
M. W. Lister
Keyword(s):  
Infrared Spectrum ◽  
Copper Complex ◽  
Rate Constants ◽  
Equilibrium Constants ◽  
Catalytic Decomposition ◽  
Quantitative Correlation ◽  
Cobalt Nickel ◽  
Nickel Copper ◽  
The Stability ◽  
Formation Of Complexes

The decomposition of acetonedicarboxylic acid at various pH and in the presence of cobalt, nickel, copper, and zinc perchlorates as catalysts has been investigated. In addition the equilibrium constants for the formation of complexes between the metal ions and the acetonedicarboxylate ion have been measured.The copper complex appears to differ from the others in being more acidic, and also in its infrared spectrum. The kinetic results have been interpreted in terms of rate constants for the decomposition of each of the complexes, and a qualitative (but not a quantitative) correlation seems to exist between the rate constants and the stability constants of the complexes.

The Effect of Aromatic Amines on the Catalyzed Decarboxylation of 3-Oxo-glutaric Acid

1972 ◽  
Vol 50 (22) ◽  
pp. 3573-3586 ◽  
Author(s):  
K. N. Leong ◽  
M. W. Lister
Keyword(s):  
Ionic Strength ◽  
Stability Constants ◽  
Rate Constants ◽  
Aromatic Amines ◽  
Copper Complexes ◽  
Glutaric Acid ◽  
Equilibrium Constants ◽  
Nickel Compound ◽  
Ph Measurements ◽  
Cobalt Nickel

Equilibrium constants have been measured for the formation of MA species, where M is divalent manganese, cobalt, nickel, or zinc, and A2− is the 3-oxo-glutarate ion. Equilibrium constants have also been measured for the reactions [Formula: see text], where B is 2,2′-bipyridyl or 1,10-phenanthroline. These constants were obtained by pH measurements at 25 °C and an ionic strength of 0.60. The results are compared with those for similar systems, especially as regards the tendency to form ternary mixed complexes of the type MAB.The rates of decarboxylation of the various MA and MAB species have been measured. The resulting rate constants follow the Irving–Williams order for stability constants, except that in both MAB species the cobalt compound decomposed slightly faster than the nickel compound. The aromatic base, which had been found earlier to have very little effect in copper complexes, increased the rate constants appreciably with other metals, especially with manganese and zinc. Usually 1,10-phenanthroline has a larger effect than 2,2′-bipyridyl. Some possible explanations of the results are considered.

scholarly journals The catalytic decomposition of sodium hypochlorite by cobalt peroxide

1923 ◽  
Vol 104 (724) ◽  
pp. 134-152 ◽  
Keyword(s):  
Sodium Hypochlorite ◽  
Silver Oxide ◽  
Catalytic Decomposition ◽  
Metallic Oxides ◽  
Bleaching Powder ◽  
Cobalt Nickel ◽  
Nickel Copper ◽  
Barium Peroxide ◽  
Continuous Stream ◽  
Evolution Of Oxygen

There are frequent references in the literature to the decomposition of hypochlorite solutions on keeping or by heating, and to their decomposition by light. The first mention of their decomposition by metallic oxides is by Balard (1) who observed that in the presence of silver oxide hypochlorites are decomposed with evolution of oxygen. Gay Lussac (2) found a similar decomposition in the presence of powdered pyrolusite, and this was confirmed by Mitscherlich (3). Fleitmann (4) suggested warming hypochlorite solutions with the oxides of cobalt, nickel, copper or iron as a means of preparing oxygen, and Bidet (5) described a method of obtaining a continuous stream of oxygen by the action of cobalt oxide on bleaching powder. Böttger (6) has examined the action of barium peroxide.

THE STABILITY OF METALLIC COMPLEXES OF TWO DIMETHYLPHENANTHROLINES

1963 ◽  
Vol 41 (5) ◽  
pp. 1135-1141 ◽  
Author(s):  
D. A. Brisbin ◽  
W. A. E. Mcbryde
Keyword(s):  
Ionic Strength ◽  
Cobalt Complexes ◽  
Formation Constants ◽  
Iron Cobalt ◽  
Cobalt Nickel ◽  
Nickel Copper ◽  
Bivalent Iron ◽  
The Stability ◽  
Partition Method ◽  
Stepwise Formation

The stepwise formation constants for the complexes formed by 5,6-dimethyl- and 4,7-dimethyl-1,10-phenanthroline with bivalent iron, cobalt, nickel, copper, and zinc were determined by a partition method. The measurements were made at 25 °C and in aqueous solutions having an ionic strength maintained at 0.1. The enhanced basicity of the ligands compared to the parent phenanthroline is paralleled by increased stability of the metallic complexes. The abnormally high formation constants of the cobalt complexes suggest oxidation to cobalt (III).

Détermination de la stabilité du complexonate peu soluble à partir des données pH-métriques

2001 ◽  
Vol 79 (7) ◽  
pp. 1166-1172 ◽  
Author(s):  
Igor Povar
Keyword(s):  
Stability Constant ◽  
Solubility Product ◽  
Equilibrium Constants ◽  
Equilibrium Concentration ◽  
Ion Selective Electrodes ◽  
Initial Composition ◽  
Good Accord ◽  
The Stability ◽  
Formation Of Complexes

A new method has been developed for the determination of the solubility product of complexonate of known composition; because of the initial composition of the heterogeneous mixture (lot a), it uses only the equilibrium values of the pH. For the determination of the stability constant in solution, these data have been completed with information on the solubility of the precipitate. We have shown that, on the basis of lot a and in the absence of reactions of formation of complexes in solution, it is possible to evaluate the equilibrium constants, since they are residuals of the compositions of the precipitate. We conclude on the possibility of applying this method to the test and standardization of ion-selective electrodes. The qualities and defect of the method are discussed. Otherwise, the values for the equilibrium constants and the equilibrium as well as the residual concentrations that we have calculated for a series of real systems from known experimental data are in good accord with those reported in tables under the same conditions.Key words: potentiometric method, heterogeneous system, slightly soluble complexonate, complexone, equilibrium concentration, solubility product, stability constant, hydrolysis reaction.[Journal Translation]

Oxidation of (1-hydroxybenzyl)ferrocene and its derivatives substituted in phenyl ring with bis(triphenylsilyl) chromate

1982 ◽  
Vol 47 (12) ◽  
pp. 3375-3380 ◽  
Author(s):  
Jaroslav Holeček ◽  
Karel Handlíř ◽  
Milan Nádvorník ◽  
Milan Vlček
Keyword(s):  
Linear Dependence ◽  
Rate Constants ◽  
Oxidation Rate ◽  
Phenyl Ring ◽  
Equilibrium Constants ◽  
Aprotic Solvents ◽  
Protonation Equilibrium ◽  
Oxidation Of Alcohols ◽  
Hammett Σ Constants ◽  
Sulphuric Acid Medium

Kinetics have been studied of oxidation of (1-hydroxybenzyl)ferrocenes substituted in phenyl ring with bis(triphenylsilyl) chromate in benzene solutions as well as protonation of these alcohols in sulphuric acid medium. Logarithms of the oxidation rate constants (kobs, 20-40 °C) and those of the protonation equilibrium constants (KR+, 25 °C) show linear dependence on the Hammett σ constants, the ρ constant values being -0.86 to -0.40 and -2.50, respectively. These negative values suggest that the both processes are influenced by the same effects and confirm the mechanism proposed earlier for oxidation of alcohols with ferrocenyl substituent by action of bis(triphenylsilyl) chromate in aprotic solvents.

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

Instability of Solutions of Quaternary Ammonium Permanganates in Dichloromethane

1997 ◽  
Vol 62 (6) ◽  
pp. 849-854 ◽  
Author(s):  
Vladislav Holba ◽  
Renata Košická
Keyword(s):  
Ammonium Salt ◽  
Rate Constants ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Activation Parameters ◽  
The Stability

The paper deals with instability of solutions of quaternary ammonium permanganates, QMnO4 (Q = tetraethyl-, tetra-1-propyl-, tetra-1-butyl-, tetra-1-pentyl-, tetra-1-octyl-, and cetyltrimethylammonium), in dichloromethane and presents the rate constants and activation parameters of the reduction of permanganate. Attention was paid to the properties of colloidal Mn(IV) intermediate. The stability of the solutions depends markedly on the quaternary ammonium salt used.

scholarly journals On the Dissolution of Metals in Ionic Liquids 1. Iron, Cobalt, Nickel, Copper, and Zinc

2021 ◽  
Vol 2 (1) ◽  
pp. 63-73
Author(s):  
Jéssica D. S. Vicente ◽  
Domingas C. Miguel ◽  
Afonso M. P. Gonçalves ◽  
Diogo M. Cabrita ◽  
José M. Carretas ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Redox Potential ◽  
Final State ◽  
Iron Cobalt ◽  
Influence Of Temperature ◽  
Dissolution Reaction ◽  
Cobalt Nickel ◽  
Iron Metal ◽  
Copper And Zinc ◽  
Nickel Copper

Ionic liquids are critical reagents for science and technical processes nowadays. Metals are the most used reagents in the industry. It is crucial to have a deeper understanding of how ionic liquids and metals could interact. In this article the interaction of those two families of compounds is accessed. The dissolution (reaction) of metals with ionic liquids is studied, namely the influence of temperature, redox potential, and availability of an oxidant in the process. The final state achieved by the iron metal samples was also addressed by Mössbauer spectroscopy.

scholarly journals Rate constants and equilibrium constants for binding of actin to the 1:1 gelsolin-actin complex

1991 ◽  
Vol 202 (3) ◽  
pp. 1127-1131 ◽  
Author(s):  
Beate SCHOEPPER ◽  
Albrecht WEGNER
Keyword(s):  
Rate Constants ◽  
Equilibrium Constants
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