scholarly journals Influence of the acidity of the iodous acid solution system on the kinetics of the disproportionation reaction

2021 ◽  
pp. 2-2
Author(s):  
Smiljana Marković
Keyword(s):  
Acid Solution ◽  
Rate Constants ◽  
Disproportionation Reaction ◽  
Solution System ◽  
Experimental Conditions ◽  
Reaction Rate Constants ◽  
Quasi Stationary State ◽  
Equilibrium Concentrations ◽  
Increasing Temperature ◽  
Equilibrium Dissociation

Influence of the acidity of the iodous acid (HOIO) solution system on the kinetics disproportionation reaction is examined in aqueous sulfuric acid solution (0.125 moldm-3 ). The disproportionation reaction rate constants were determined at 285, 291, 298 and 303 K based on data obtained under stationary conditions. The calculated rate constants increase with increasing temperature for different values of iodous acid and iodate concentrations. The average activation energy of 46 kJmol-1 was determined for the chosen temperature interval, by a graphical method. The values of pseudo-equilibrium concentrations of kinetically important and catalytic species H+ , H2OI+ i IO3 - in the disproportionation reaction were determined for the given experimental conditions based on the equilibrium dissociation reactions of sulfuric and iodous acids in the quasi-stationary state. The estimated values of sulfuric and iodous acid are predominant and higher than the concentration of the protonated ion of H2OI+ .

scholarly journals The kinetics of the reactions of 2-substituted nicotinic acids with diazodiphenylmethane in various alcohols

2003 ◽  
Vol 68 (7) ◽  
pp. 515-524 ◽  
Author(s):  
Sasa Drmanic ◽  
Bratislav Jovanovic ◽  
Aleksandar Marinkovic ◽  
Milica Misic-Vukovic
Keyword(s):  
Hydrogen Bond ◽  
Rate Constants ◽  
Linear Regression Analysis ◽  
Solvent Polarity ◽  
Multiple Linear Regression Analysis ◽  
Hydrogen Bond Donor ◽  
Initial State ◽  
Experimental Conditions ◽  
Hydrogen Bond Acceptor ◽  
Reaction Rate Constants

The rate constants of 2-substituted nicotinic acids in reaction with diazodiphenylmethane (DDM) in eight alcohols at 30 ?C have been determined. In order to explain the obtained results through solvent effects, the second order reaction rate constants (k) of the examined acids were correlated using the appropriate solvent parameters by the equation: logk=logk0 af(?) + b?* + cn?H where f(?) is the measure of solvent ability as a dielectric to stabilize the separation of opposite charges in the activated complex, ?* is the measure of solvent ability to stabilize proton in the initial state and n?H represents the ability of protic solvents to form hydrogen bond with the negative end of the ion-pair intermediate. These constants were correlated also by using solvatochromic equation of the form logk=logk0 + s?* + a? + b? where ?* is the measure of the solvent polarity, ? represents the scale of the solvent hydrogen bond donor acidities (HBD) and ? represents the scale of the solvent hydrogen bond acceptor basicities (HBA). The correlations of the kinetic data were carried out by means of multiple linear regression analysis. The results obtained for 2-substituted nicotinic acids were compared with the results for ortho-substituted benzoic acid under the same experimental conditions.

scholarly journals Prediction of esterification rate constants for secondary alkan-2-ols based on one- and two-parameter Taft equations

2020 ◽  
Vol 45 ◽  
pp. 146867831989184
Author(s):  
Ján Vojtko ◽  
Jaroslav Durdiak ◽  
Zuzana Lukáčová-Chomisteková ◽  
Peter Tomčík
Keyword(s):  
Rate Constants ◽  
Equilibrium Constants ◽  
Correlation Equation ◽  
Reaction Rates ◽  
Experimental Conditions ◽  
Monocarboxylic Acids ◽  
Reaction Rate Constants ◽  
Inductive Effects ◽  
Esterification Rate ◽  
Two Parameter

Equilibrium constants and reaction rate constants for the esterification of secondary alkan-2-ols with acetic acid were measured at 60°C in 1,4-dioxane. Taft coefficients, as single parameter (without inductive effects), and two-parameter correlation (including inductive and steric effects), of the measurements were used for the prediction of esterification rate constants for secondary alkan-2-ols with monocarboxylic acids. For this prediction, previously observed results of linear correlation of rate constants for the esterification of propan-1-ol with monocarboxylic acids measured under identical experimental conditions were applied. Two parameter Taft equations for the correlation of secondary alkan-2-ols and for monocarboxylic acids were combined, resulting in an overall correlation equation usable for the prediction of reaction rates for secondary alkan-2-ols with any monocarboxylic acid. This equation was experimentally verified for the esterification of three randomly chosen alkan-2-ols with three randomly chosen monocarboxylic acids.

Formation of BrO2 in the Belousov-Zhabotinsky-System — Investigation of the HBrO2 /BrO3–-Reaction

1980 ◽  
Vol 35 (12) ◽  
pp. 1354-1360 ◽  
Author(s):  
H. D. Försterling ◽  
H. J. Lamberz ◽  
H. Schreiber
Keyword(s):  
Sulfuric Acid ◽  
Acid Solution ◽  
Equilibrium Constant ◽  
Sulfuric Acid Solution ◽  
Rate Constants ◽  
Maximum Concentration ◽  
Spectral Dependence ◽  
Disproportionation Reaction ◽  
A Value

The reaction between HBrO2 and bromate was studied in sulfuric acid solution. From the spectral dependence of the absorbance in the region from 400 to 600 nm it is concluded that BrO2 is an intermediate of the reaction. From the maximum concentration of BrO2 the equilibrium constant of the BrO2/Br2O4-equilibrium is evaluated; furthermore, a value for the ratio of the rate constants for the HBrO2/BrO3--reaction and the disproportionation reaction of HBrO2 is given.

Measurement of the OH Reaction Rate Constants for CF3CH2OH, CF3CF2CH2OH, and CF3CH(OH)CF3

1999 ◽  
Vol 103 (15) ◽  
pp. 2664-2672 ◽  
Author(s):  
Kazuaki Tokuhashi ◽  
Hidekazu Nagai ◽  
Akifumi Takahashi ◽  
Masahiro Kaise ◽  
Shigeo Kondo ◽  
...  
Keyword(s):  
Rate Constants ◽  
Reaction Rate ◽  
Reaction Rate Constants
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