Investigation of molecular interactions in binary mixture of dimethyl carbonate plus N-methylformamide at T = (303.15, 308.15, 313.15 and 318.15) K

摘要

Density (rho) and speed of sound (u) of binary liquid mixtures of dimethyl carbonate and N-methylformamide have been determined at T = (303.15, 308.15, 313.15 and 318.15) K over the entire composition range. Experimental data are used to evaluate excess values of molar volume (), isentropic compressibility (), isothermal compressibility (), intermolecular free length (), acoustic impedance () and ultrasonic speed (). The V (E) data in the present investigation were analysed by using Prigogine-Flory-Patterson (PFP) theory. Partial and excess partial molar volumes (, ), (, ) and partial and excess partial molar volume of the components at infinite dilution (, ), (, ) at T = (303.15, 308.15, 313.15, 318.15) K have been calculated. The excess/deviation properties were fitted to Redlich-Kister equation to obtain their coefficients and standard deviations. The present investigation also comprises the acoustic nonlinearity parameter (B/A) in the mixtures and calculation of cohesive energy , Van der Wall's constants (a, b) and distance of closest approach (d). Moreover, various semi-empirical relations of ultrasonic speed have been used to correlate the theoretical velocities. FT-IR spectra of pure components and their binaries have been measured at T = 298.15 K.