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The solubility of triazolo quinolone class derivatives in methanol, ethanol, n-propanol, n-butanol and ethyl acetate was measured using a gravimetrical method at temperature ranging from 298.15 K to 328.15 K. The results of these measurements were correlated with semi empirical equations. Some thermodynamic parameters such as dissolution enthalpy, Gibb’s free energy and entropy of mixing have also been calculated.

The solubility of Alloxan in methanol, ethanol, ethane-1, 2 diol, water, acetone and tetrahydrofuran was measured by gravimetric method over a temperature range (293.15 to 323.15) K at atmospheric pressure. The solubility increases non-linearly with temperature in all the studied solvents. Further, in protic solvents, solubility is maximum in methanol and minimum in ethane-1, 2 diol whereas in the selected non protic solvents, solubility is greater in tetrahydrofuran than in acetone. The experimental data were correlated with modified Apelblat and Buchowski-Ksiazczak equations. The calculated results show good agreement with the experimental data. Some apparent thermodynamic parameters such as dissolution enthalpy, Gibb's free energy, and entropy of mixing have also been calculated. The evaluated thermodynamic parameters are found to be positive. The positive enthalpy and Gibb's free energy indicate endothermic and spontaneous dissolution of compounds. The positive entropy suggests entropy-driving dissolution process.

Ultrasonic velocity, density and viscosity of some synthesized chalcones were measured in N,N-dimethyl formamide and chloroform at different temperatures (298.15 to 318.15 K). From these experimental data, various acoustical parameters such as specific impedance (Z), adiabatic compressibility (κs), Rao’s molar sound function (Rm), intermolecular free path length (Lf), solvation number (Sn), internal pressure (π) have been calculated in order to understand the molecular interactionsin the studied solutions. The results are interpreted in terms of molecular interactions occurring in the solutions. La velocidad ultrasónica, la densidad y la viscosidad de soluciones de algunas chalconas sintéticas se midieron en N, N-dimetilformamida y cloroformo a diferentes temperaturas (desde 298,15 hasta 318,15 K). A partir de estos datos experimentales, se calcularon diversos parámetros acústicos tales como la impedancia específica (Z), la compresibilidad adiabática (ks), la función de sonido molar de Rao (Rm), la longitud de trayecto libre intermolecular (Lf), el número de solvatación (Sn) y la presión interna (Π), para comprender las interacciones moleculares en las soluciones estudiadas. Los resultados se interpretan en términos de las posibles interacciones moleculares que ocurren en las soluciones.

Some physicochemical parameters such as density refractive index and conductance of some newly synthesized pyrimidine derivatives have been measured in N N dimethyl formamide chloroform and methanol at K It is observed that these studied parameters depend on the solvent and structure of compounds which may be due to different type of interactions