Effect of Arrhenius energy factor on molecular interactions of binary liquid mixtures

Abstract

Density (ρ) and speed of sound (u) data have been measured at temperatures 298.15 and 318.15 K and at atmospheric pressure for binary mixtures of aniline with toluene and isomeric chlorotoluenes namely o-chlorotoluene (oct), m-chlorotoluene (mct), p-chlorotoluene (pct) over the entire composition range. Experimental density and speed of sound data (u) have been used to calculate the excess volumes (VE), isentropic compressibilities (κs), excess isentropic compressibilities (κ s E ), excess intermolecular free length (L f E ), deviation in sound speed (Δu), and excess acoustic impedance (ZE) were computed for all mixtures. The results have been used to explore molecular interactions and structural effects which are prevailing between component molecules. The experimental speed of sound data was analyzed in terms of Schaaff’s collision factor theory and Jacobson’s free length theory to test their relative predicting ability in terms of pure component liquids. Also, apparent molar volume ( $$\overline{V}_{{\varphi ,{\text{i}}}}^{{}}$$ ) and partial molar volume ( $$\overline{V}_{\text{i}}^{{}}$$ ), excess partial molar volume, ( $$\overline{V}_{\rm i}^{\rm E}$$ ) and their limiting values at infinite dilution, $$\overline{V}_{\rm{\varphi ,i}}^{ \circ }$$ , $$\overline{V}_{\rm i}^{ \circ }$$ and $$\overline{V}_{\rm m,i}^{\rm{E,\infty }}$$ , and partial isentropic compressibility ( $$\overline{\kappa }_{\rm i}^{{}}$$ ), excess partial isentropic compressibility ( $$\overline{\kappa }_{\rm i}^{\rm E}$$ ) and their limiting values at infinite dilution, $$\overline{\kappa }_{\varphi , {\rm i}}^{ \circ }$$ , $$\overline{\kappa }_{\rm i}^{ \circ }$$ and $$\overline{\kappa }_{\rm m,{\rm i}}^{E,\infty }$$ , respectively, have been calculated from the experimental density measurements. The variation of thermal properties with composition and temperature of the mixtures was analyzed in terms of molecular interactions.