Kinetics of oxidation of the bis(ethylenediamine)mercaptoacetatocobalt(III) and cysteinato-bis(ethylenediamine)cobalt(III) ions by hydrogen peroxide in mixed aqueous-nonaqueous solutions

1988 ◽  
Vol 53 (3) ◽  
pp. 554-562
Author(s):  
Ján Benko ◽  
Oľga Vollárová ◽  
Miroslav Kovarčík
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Rate ◽  
Activation Parameters ◽  
Butyl Alcohol ◽  
Acid Base ◽  
Kinetics Of Oxidation ◽  
Tert Butyl Alcohol ◽  
Alcohol Water ◽  
Acid Base Equilibrium ◽  
Kinetics Of

The kinetics of oxidation of the coordinatively bonded sulphur in the cysteinato-bis(ethylenediamine)cobalt(III) and bis(ethylenediamine)mercaptoacetatocobalt(III) complexes by hydrogen peroxide to the sulphoxides was examined in HClO4 solutions (c(HClO4) = 1 – 500 mmol l-1) with a view to obtaining data characterizing the effect of the acid-base equilibria of the reactants on the reaction rate. The reaction rate was found affected particularly by the acid-base equilibrium of the oxidant, which plays a role in strongly acid solutions. The oxidation was also studied in water-methyl alcohol, water-tert-butyl alcohol and water-ethylene glycol mixtures, and the effect of the mole fraction of the nonaqueous component on the rate constant and thermodynamic activation parameters was examined.

Thermodynamic and Kinetic Investigation of the Solvent Effect on the Oxidation of [Co(en)2SCH2COO]+ with S2O82- In Water-Methanol and Water-tert-Butyl Alcohol Mixtures

1993 ◽  
Vol 58 (5) ◽  
pp. 1001-1006 ◽  
Author(s):  
Oľga Vollárová ◽  
Ján Benko
Keyword(s):  
Transfer Functions ◽  
Activation Parameters ◽  
Butyl Alcohol ◽  
Oxidation Of Co ◽  
Kinetics Of Oxidation ◽  
Tert Butyl ◽  
Tert Butyl Alcohol ◽  
Alcohol Mixtures ◽  
Kinetics Of

The kinetics of oxidation of [Co(en)2SCH2COO]+ with S2O82- was studied in water-methanol and water-tert-butyl alcohol mixtures. Changes in the reaction activation parameters ∆H≠ and ∆S≠ with varying concentration of the co-solvent depend on the kind of the latter, which points to a significant role of salvation effects. The solvation effect on the reaction is discussed based on a comparison of the transfer functions ∆Ht0, ∆St0 and ∆Gt0 for the initial and transition states with the changes in the activation parameters accompanying changes in the CO-solvent concentration. The transfer enthalpies of the reactant were obtained from calorimetric measurements.

A KINETICS AND MECHANISTIC STUDY OF THE OXIDATION OF L-ARGININE BY QDC IN DMF-WATER MEDIUM

2021 ◽  
pp. 11-12
Author(s):  
Deepika Jain ◽  
Shilpa Rathor
Keyword(s):  
Perchloric Acid ◽  
Reaction Rate ◽  
Main Product ◽  
Activation Parameters ◽  
Reaction Rates ◽  
Mechanistic Study ◽  
Water Medium ◽  
Volume Percentage ◽  
Kinetics Of Oxidation ◽  
Kinetics Of

The present paper describes the kinetics of oxidation of l-Arginine by QDC in the presence of perchloric acid in 30% DMF-H O(v/v) medium at 2 + 40⁰C spectrophotometrically at λ =354nm. The reaction is rst order with respect to [QDC], [H ], and [substrate]. The reaction rate increased with max increasing volume percentage of DMF in reaction mixture. Michaelis- Menten type kinetic was observed with l-Arginine. The reaction rates were studied at different temperature and the activation parameters has been computed. The main product was identied as Cr (III) and 4-Guanidino buteraldehyde.

Kinetics and mechanism of oxidation of iodide ion by the molybdenum (VI) – hydrogen peroxide system

1990 ◽  
Vol 68 (9) ◽  
pp. 1499-1503 ◽  
Author(s):  
Conchita Arias ◽  
Fernando Mata ◽  
Joaquin F. Perez-Benito
Keyword(s):  
Hydrogen Peroxide ◽  
Rate Constants ◽  
Reaction Rate ◽  
Sodium Molybdate ◽  
Initial Reaction Rate ◽  
Initial Reaction ◽  
Kinetics Of Oxidation ◽  
Iodide Ion ◽  
Aqueous Perchloric Acid ◽  
Kinetics Of

The kinetics of oxidation of potassium iodide by hydrogen peroxide in aqueous perchloric acid has been studied both in the absence and in the presence of sodium molybdate by means of the initial-rates method. The law found for the total initial reaction rate is[Formula: see text]The activation energies associated with rate constants k1, k2, and k3 are 52 ± 1, 49 ± 1, and 42 ± 3 kJ mol−1, respectively. A mechanism in agreement with the experimental kinetic data is proposed, according to which rate constants k1, k2, and k3 correspond to the oxidations of iodide ion by H2O2, H3O2+ and H2MoO5, respectively. Keywords: catalysis, hydrogen peroxide, iodide ion, kinetics, molybdate ion.

Kinetics of oxidation of cis-bis(ethylenediamine)isothiocyanatonitrocobalt(III) ion with peroxodisulphate

1979 ◽  
Vol 44 (12) ◽  
pp. 3588-3594 ◽  
Author(s):  
Vladislav Holba ◽  
Olga Volárová
Keyword(s):  
Ionic Strength ◽  
Rate Constants ◽  
Oxidation Kinetics ◽  
Reaction Rate ◽  
Salt Effect ◽  
Activation Parameters ◽  
Reaction Products ◽  
Kinetics Of Oxidation ◽  
Thermodynamic Activation Parameters ◽  
Kinetics Of

The oxidation kinetics of cis-bis(ethylenediamine)isothiocyanonitrocobalt(III) ion with peroxodisulphate was investigated in the medium of 0.01 M-HClO4 in dependence on the ionic strength and temperature and the reaction products were identified. Extrapolated values of thermodynamic activation parameters were determined from the temperature dependence of the rate constants extrapolated to zero ionic strength. The distance of the closest approach was estimated for the reacting ions by evaluating the primary salt effect. To elucidate the mechanism, the influence of the cyclic polyether 18-crown-6 on the reaction rate was followed.

Kinetics of oxidation of bis(ethylenediamine)mercaptoacetatocobalt(III) and cysteinatobis(ethylenediamine)cobalt(III) ions by peroxodisulphate in aqueous-nonaqueous mixed solvents

1986 ◽  
Vol 51 (5) ◽  
pp. 1049-1060 ◽  
Author(s):  
Oľga Vollárová ◽  
Ján Benko ◽  
Ivana Matejeková
Keyword(s):  
Perchloric Acid ◽  
Transfer Functions ◽  
Mixed Solvents ◽  
Sodium Perchlorate ◽  
Activation Parameters ◽  
Solvent System ◽  
Butyl Alcohol ◽  
Complex Ions ◽  
Kinetics Of Oxidation ◽  
Kinetics Of

The kinetics of oxidation in the first step was studied for coordination-bonded sulphur in the cysteinatobis(ethylenediamine)cobalt(III) and bis(ethylenediamine)mercaptoacetatocobalt(III) ions using peroxodisulphate as oxidant. The effect of the acid-base equilibria of the reactants was established based on the dependences of the rate constant and the thermodynamic activation parameters ΔH and ΔS on perchloric acid concentration. The effect of ionic strength at various perchloric acid concentrations, was examined for the two complex ions. The combined effect of perchloric acid and sodium perchlorate was investigated in water-tert-butyl alcohol and water-ethylene glycol solutions. The transfer functions were calculated from the changes in the solubility of the reactants on passing from aqueous to the mixed aqueous-nonaqueous solutions, and the role of solvation during the oxidation of the complexes by peroxodisulphate was assessed based on the dependences of the transfer functions on the nonaqueous component content of the solvent system.

scholarly journals Kinetics and Mechanism of Oxidation of Isoleucine byN-Bromophthalimide in Aqueous Perchloric Acid Medium

2011 ◽  
Vol 8 (4) ◽  
pp. 1728-1733 ◽  
Author(s):  
N. M. I. Alhaji ◽  
S. Sofiya Lawrence Mary
Keyword(s):  
Acid Medium ◽  
Perchloric Acid ◽  
Reaction Rate ◽  
Activation Parameters ◽  
Halide Ions ◽  
Kinetics Of Oxidation ◽  
First Order ◽  
Hypobromous Acid ◽  
Different Temperatures ◽  
Kinetics Of

The kinetics of oxidation of isoleucine withN-bromophthalimide has been studied in perchloric acid medium potentiometrically. The reaction is of first order each in [NBP] and [amino acid] and negative fractional order in [H+]. The rate is decreased by the addition of phthalimide. A decrease in the dielectric constant of the medium increases the rate. Addition of halide ions or acrylonitrile has no effect on the kinetics. Similarly, variation of ionic strength of the medium does not affect the reaction rate. The reaction rate has been determined at different temperatures and activation parameters have been calculated. A suitable mechanism involving hypobromous acid as reactive species has been proposed.

Sign in / Sign up

Export Citation Format

Share Document