Volumetric and acoustic properties of binary mixtures of cyclohexane + benzene and + benzaldehyde at (293.15–323.15) K

Densities ρ of and speeds of sound u in binary mixtures cyclohexane + benzene and + benzaldehyde have been measured over the entire range of composition at atmospheric pressure and at temperatures ranging from (293.15 to 323.15) K using an Anton-Paar DSA 5000. From these data molar isentropic compressibilities KS,m, thermal expansion coefficients αP, excess molar volumes image, and excess molar isentropic compressibilities image at all the temperatures, and excess thermal expansion coefficients image and isothermal pressure coefficient of excess molar enthalpy image at 298.15 K were calculated. The image for both the mixtures are positive at all temperatures and over entire range of compositions. The image are positive over entire composition for cyclohexane + benzene while image curve is S-shaped for cyclohexane + benzaldehyde. The values of image are negative except for cyclohexane rich region in both the mixtures. The values of all the excess functions are lower for cyclohexane + benzaldehyde as compared to cyclohexane + benzene at all the temperatures and compositions.