; AJC-14489 Density (ρ), viscosity (η) and ultrasonic velocity (U) have been measured for a binary mixture composed of methyl formate and methanol at 303, 308 and 313 K. The adiabatic compressibility (β), acoustic impedance (Z), free length (Lf), free volume (Vf), internal pressure (πi), viscous relaxation time (τ) and Gibbs free energy (∆G) have been calculated from the experimental data. The excess values of these parameters (β E , Z E , Lf E , Vf E , πi E , τ E and ∆G E) have also been calculated by using the determined data and interpreted in terms of molecular interactions. The deviations in the sign and values of these excess parameters from the ideal mixing reveal that intermolecular interactions obtaining in the liquid mixture.