Temperature dependence of densities, speeds of sound, and derived properties of cyclohexylamine + cyclohexane or benzene in the temperature range 293.15–323.15 K

Densities ρ and speeds of sound u for binary mixtures cyclohexylamine + cyclohexane and +benzene have been measured over the entire range of composition at temperatures from 293.15 to 323.15 K using an Anton-Paar DSA 5000. The molar isentropic compressibilities KS,m, Rao's molar sound functions R, thermal expansion coefficients αP, excess molar volumes VmE, and excess molar isentropic compressibilities KS,mE have been calculated from these data. VmE and KS,mE for both the mixtures are positive at all temperatures and over entire range of compositions. The values of VmE for cyclohexylamine + cyclohexane increase with rise in temperature while decrease for cyclohexylamine + benzene. The values of αPE are positive for cyclohexylamine + cyclohexane and negative for cyclohexylamine + benzene. The results of u  , VmE, (∂VmE/∂T)P, and (∂HmE/∂P)T are compared with the theoretical predictions of the Prigogine–Flory–Patterson theory.

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► Experimental data in between T = 293.15 and 323.15 K at 5 K interval.
► Volumetric and acoustic properties of binary mixtures involving cyclohexylamine.
► Thermal expansion coefficient and pressure dependence of excess enthalpy calculated.
► Excess molar volume and speed of sound estimated using the PFP theory.
► Prediction of ∂VmE/∂TP and (∂HmE/∂P)T by the PFP theory is not satisfactory.