Thermodynamic Studies on Ion Association of Lithium Chloride and Lithium Nitrate in Acetonitrile + Water Mixed Solvents at Different Temperatures

The present study reports the ion association of lithium chloride (LiCl) and lithium nitrate (LiNO3) electrolytes in acetonitrile + water (AN+W) mixtures at 283.15 K to 311.15 K. Their limiting molar conductance (Λo), the association constant values (KA) for their different mole fractions, i.e. 0.0000, 0.0588, 0.1233, 0.1942, 0.2727, 0.3600, 0.4576, 0.5676, 0.6923, 0.8351 and 1.0000 have been evaluated using Shedlovsky technique. The KA and Walden products (Λoηo) for LiCl and LiNO3 salts have been calculated in the acetonitrile-water solvent at experimental temperatures. The calculated values qualitatively examined the possible nature of the solvent-solvent, their ion-ion, and ion-solvent and interactions of the two selected compounds mixed solvents of (acetonitrile + water). Then dependence of KA temperature has also been investigated to obtain the thermodynamic functions of different parameters, such as ΔGº, ΔSº, ΔHº and Ea, as a function of the mixed composition of the composition solvents AN+W (acetonitrile + water).

Evaluation of the physical parameters of nano-sized tetrachlorosilane as an inorganic material a mixed solvent using Fuoss-Shedlovsky and Fuoss-Hsia-Fernández-Prini techniques

The electrical conductance of nano-sized tetrachlorosilane is measured in 50% mixed solvent of (absolute ethanol-H2O) at various temperatures. The Λ0 (limiting molar conductance) and the KA (association constant) are evaluated via using Fuoss-Shedlovsky (F-SH) and Fuoss-Hsia-Fernández-Prini (FHFP) theories. The standard thermodynamic parameters for association (ΔS°A, ΔH°A& ΔG°A), energy of activation (Ea), hydrodynamic radii (RH) and Walden product (Λ0 η0) are calculated for tetrachlorosilane. These various physical parameters for tetrachlorosilane are evaluated and discussed.

Ion-Conductance and Solvation Behavior of Benzyl Trimethyl Ammonium Chloride in Aqueous-Methanol Mixtures

Ion-conductance and solvation conduct associated with diverse electrolytes in solvents is recited to be shaped by numerous aspects like density, viscosity, dielectric constant of medium, ion-solvent relations and solvent-solvent actions. Ion-solvent interactions soothe the ion by solvating it. Conductance statistics and viscosity numbers of distant electrolytes is of use in analyzing the ion solvent relations and solvation behavior of the ions. Conductance and ion-solvation behavior of benzyl trimethyl ammonium chloride has been measured in aqueous methanol and aqueous dimethyl formamide of different composition in the temperature range of 283K to 318K. Limiting molar conductance dissociation constant of the ion pair, KC are figured using Fuoss-Kraus Limiting Law. 0 rise with percentage of water in the solvent fusion. KC value is highest in pure aqueous solvent. Walden product is highest in 20% aqueous-methanol mixture signifying that ion-solvent interactions are highest at this composition of solvent combination and Walden .product as a function of the specific ion-solvent interactions including structural effects.

Conductometric Study of Nimesulide in Aqueous Solutions of Hydrotropic Agents at Different Temperatures

Conductance values of nimesulide have been determined in water in 0.1, 0.2, 0.4, 0.6, 0.8, 1 and 2 mol dm-3aqueous solutions of hydrotropic agents (sodium benzoate, sodium salicylate, sodium bromide and nicotinamide) at temperatures 298.15, 303.15, 308.15 and 313.15 K. The conductance values have been used to evaluate the limiting molar conductance and association constants by means of Shedlovsky extrapolation technique. Thermodynamic parameters for the association process of nimesulide in aqueous solutions of hydrotropic agents have also been calculated.

Conductometric Study of Some Tetraalkylammonium Bromides in 2-Ethoxyethanol in the Temperature Range 35–50 °C

The electrical conductances of the solutions of four tetraalkylammonium bromide salts (R4NBr), namely tetraethylammonium bromide (Et4NBr), tetrapropylammonium bromide (Pr4NBr), tetrapentylammonium bromide (Pen4NBr) and tetraheptylammonium bromide (Hep4NBr) in 2-ethoxyethanol have been reported at 35, 40, 45 and 50 °C. The conductance data have been analyzed by the 1978 Fuoss conductance–concentration equation in terms of the limiting molar conductance (Λ0), the association constant (KA) and the association diameter (R). The ionic contributions to the limiting molar conductance have also been estimated. Appreciable ionic association was observed for all of these electrolytes in 2-ethoxyethanol. The tetraalkylammonium ions (R4N+) were found to remain scarcely solvated in the present solvent medium within the temperature range investigated here. The solvation of the bromide ion in these tetraalkylammonium bromide is found to be weakened as soon as the ion-pairs are formed. An increase in the temperature results in a lower level of ion-pairing for each of these salts.

Electrical Conductances of Tetrabutylammonium Bromide, Sodium Tetraphenylborate and Sodium Bromide in 2-Ethoxyethanol in the Temperature Range 35–50°C

The electrical conductances of the solutions of tetrabutylammonium bromide (Bu4NBr), sodium tetraphenylborate (NaPh4B) and sodium bromide (NaBr) in 2-ethoxyethanol have been reported at 35, 40, 45 and 50°C. The conductance data have been analyzed by the 1978 Fuoss conductance–concentration equation in terms of the limiting molar conductance (Λ0), the association constant (KΛ) and the association diameter (R). The ionic contributions to the limiting molar conductances (Λ0) have been estimated using the “reference electrolyte” tetrabutylammonium tetraphenylborate (Bu4NPh4B). Appreciable ionic association was observed for all of these electrolytes which were found to exist in the form of solvent-separated ion-pairs in 2-ethoxyethanol. The tetrabutylammonium and tetraphenylborate ions are found to remain scarcely solvated whereas the sodium and bromide ions undergo substantial solvation in 2-ethoxyethanol medium in the temperature range investigated here.