Investigation of molecular interactions in binary mixtures of 2-methoxyaniline with cyclic ketones at various temperatures through thermophysical properties

Abstract

Densities (ρ) and speeds of sound (u) of binary mixtures of 2-methoxy aniline with acetophenone and cyclic ketones (cyclopentanone and cyclohexanone) including those of pure liquids, over the entire composition range, were measured at temperatures (303.15, 308.15, 313.15 and 318.15) K and atmospheric pressure 0.1 MPa. Using the experimental data, VE, $$\kappa_{\text{s}}^{\text{E}}$$ , $$\bar{V}_{\text{m,1}}^{\text{E}}$$ , $$\bar{V}_{\text{m,2}}^{\text{E}}$$ , $$\bar{K}_{\text{s,m,1}}^{\text{E}}$$ and $$\bar{K}_{\text{s,m,2}}^{\text{E}}$$ were calculated. The variation of these excess properties with the composition of the mixtures suggests hydrogen bond, dipole–dipole interactions and charge transfer complex formation between unlike molecules. The VE results have been analyzed in the light Prigogine–Flory–Patterson theory. An analysis of each of the three contributions viz. interactional, free volume and characteristic pressure $$P^{*}$$ to VE shows that interactional contribution is positive for all binary systems. The free volume effect and characteristic pressure $$P^{*}$$ contribution are negative for all the mixtures.