The ultrasonic velocity, density and viscosity have been measured for the mixtures of 1–alkanols, namely, 1–propanol, 1–butanol, and 1–pentanol in p-xylene with nitrobenzene at 303 K. The experimental data’s have been used to calculate the acoustical parameters namely adiabatic compressibility (b), free length (Lf), free volume (Vf), internal pressure (pi), and acoustic impedance (Z). The excess values of some of the above parameters are also evaluated and presented. A strong dipole-dipole interaction through hydrogen bonding between nitrobenzene and 1-alkanols is observed in the present investigation. The donor-acceptor complexation between p-xylene and nitrobenzene molecules is noticed. It is understood that the above two factors which clearly lead to an increase in adiabatic compressibility and intermolecular free length in the liquid mixtures.
