The ultrasonic velocity, density and viscosity have been measured for the mixtures of amines, namely, Di-methyl amine, Di-ethylamine and Tri-ethyl amine with amide in benzene at 303 K 313K and 323K.The experimental data have been used to calculate the thermo dynamical parameters namely adiabatic compressibility (β), free length (Lf), free volume (Vf) and internal pressure (πi) viscous relaxation time (τ) and Gibbs’ free energy (ΔG). Present study helped to find the existence of strong molecular association. Such a molecular association is found to be by hydrogen bonding and through dipole-dipole interaction