Rahul Bhalodia

Dissociation constants of some derivatives of 5-amino isophthalic acid in mixed solvents

The dissociation constants of some derivatives of 5-amino isophthalic acid have been measured by Calvin Bjerrum pH titration method in DMF-water and DMSO-water (60: 40 v/v) systems at 308.15 K. It is observed that dissociation constant depends on the solvent and substituents group present in the compound.

Study of molecular interactions in solutions of azomethines of sulfamethoxazole in N,N-dymethylformamide and tetrahydrofuran

Density, ultrasonic velocity and viscosity of azomethines containing sulfamethoxazole nucleus have been measured in N,N-dimethylformamide and tetrahydrofuran solutions over a wide concentration range at temperature 308.15 K. From these experimental data, acoustical parameters such as intermolecular free path length, isentropic compressibility and relaxation strength have been evaluated, that help understanding the molecular interactions occurring in these solutions. Furthermore, compressibility solvation number, the apparent molar compressibility and apparent molar volume of the solutions have been determined and discussed.

Determination of some thermodynamic parameters of dissociation of dihydropyrimidine derivatives

Dissociation constant of dihydropyrimidine derivatives has been determined in dimethyl forma-mide—water (60: 40 v/v) system at different temperatures. The data are discussed in terms of the electron nature of the substituents. Further, some thermodynamics parameters such as enthalpy of solution, Gibbs energy change and entropy of solution have also been evaluated for these systems.

Adiabatic compressibilities of some synthesized derivatives of dihydropyrimidines in N,N-dimethylformamide and dimethyl sulfoxide at 298.15 K

Sound velocities of solutions of some derivatives of dihydropyrimidines (DHPMs) in N,N-dimethylforamide (DMF) and dimethyl sulfoxide (DMSO) were measured at 298.15 K over a wide range of concentration. Adiabatic compressibilities, apparent adiabatic molar compressibilities and apparent adiabatic molar volumes were also evaluated. Results of sound velocity measurements provide useful information about ion-ion and ion-solvent interactions and are of significant help in understanding the behavior of electrolytes in solutions.