Kinetics of the Alkaline Solvolysis of Trichloroacetate Ion in Water-Ethanol Solutions

Abstract

<jats:title>Abstract</jats:title><jats:p> Alkaline Solvolysis, Trichloroacetate Ion The alkaline solvolysis of trichloroacetic acid in water-ethanol mixtures have been studied in the presence of 0.40-0.80 M sodium hydroxide within the temperature range 35-70 °C. The rate constant increased with progressive addition of the organic solvent. The dielectric constant effect on the reaction rate was investigated. The radius of the activated complex at different temperatures was calculated. The isocomposition and isodielectric energies as well as the thermodynamic parameters of activation were calculated and their significance in terms of solvent composition has been discussed. It was concluded that the reactant state is extensively higher solvated than the transition state by the highly polar (water) solvent.</jats:p>

Syntheses of Birnessites Using Alcohols as Reducing Reagents: Effects of Synthesis Parameters on the Formation of Birnessites

“…α-MnO(OH) was not formed in the Na + system when NaOH was mixed with sodium permanganate in water before it was added to aqueous ethanol solution. The higher solvating ability of ethanol than water, the lower cation mobility in ethanol than in water, and the stronger hydrogen bonding between water and ethanol than between water molecules , might be some of the reasons that α-MnO(OH) was not formed in the Na + system when Method 2 was used.…”

Notizen: Kinetics of the Alkaline Decarboxylation of Trichloroacetate Ion in Water - Ethanol Solutions

“…In reference to a paper [1] which appeared recently in this journal, it is appropriate to make some comments especially on the calculations of the radius of the activated complex and the discussion herewith. Although my name has been included as a coauthor of this paper, it has been written and sent to press without my seeing it.…”

“…This equation is derived and is generally applied for the situation in which the rate of formation of the activated complex is due to the reaction of an ion with charge Ze and a dipole molecule of moment /a [8][9][10], However, it is not understood why the dipole [1] for the radius of the activated complex (r*) lie within the range 2.67 to 3.1 Ä, and these are below the radius of the reactant ion which is about 3.4 Ä [6]. This result is not in concordance with the postulated reaction mechanism, according to which we expect that the volume of the transition state to be greater than the reactant state, the volume of activation to be positive, and the internal pressure of the reactant ion to be higher than that of the activated complex [5,6].…”