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 VmE, and excess molar isentropic compressibilities KS,mE at all the temperatures, and excess thermal expansion coefficients αPE and isothermal pressure coefficient of excess molar enthalpy (∂HmE/∂P)T,x at 298.15 K were calculated. The VmE for both the mixtures are positive at all temperatures and over entire range of compositions. The KS,mE are positive over entire composition for cyclohexane + benzene while KS,mE curve is S-shaped for cyclohexane + benzaldehyde. The values of αPE 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.

► Volumetric, acoustic properties of cyclohexane + benzene and + benzaldehyde.
► Excess thermal expansion coefficient & pressure dependence of excess enthalpy.
► Excess molar volumes of cyclohexane + benzene compared with literature.
► Excess volumes and speed of sound estimated from PFP theory.
► The excess functions are lower for benzaldehyde mixtures as compared to benzene.