Study of binary liquid mixture of n-decane and validation of theoretical approaches of sound speed at 298.15 K

Abstract

236-245Experimental values of densities (ρ) and speeds of sound (u) at T=298.15 K in the binary mixtures of n-decane with hexan-2-ol, heptan-2-ol and octan-2-ol are presented over the whole range of mixture composition. From these data, excess molar volumes (VmE), excess isentropic compressibility (kEs), excess intermolecular free length (LfE), excess specific acoustic impedance (ZE), excess available volume (VaE) and excess internal pressure (πE) have been calculated. These results were fitted to Redlich-Kister polynomial equations to estimate the binary coefficients and standard errors. Comparisons of theoretical ultrasonic speeds have been calculated by using collision factor theory (CFT), free length theory (FLT), Nomoto’s empirical equation (NOM), Jouyban-Acree model and Prigogine-Flory-Patterson (PFP) theory with Van der Waals (vdW) potential energy model and the results have been compared with experimental values. Extensive work is carried out to judge the best suitable model out of CFT, NOM, FLT, PEP theory and Jouyban-Acree model. The deviation from ideality of these parameters is explained on the basis of molecular interactions between components of the mixture