The viscosities, diffusion coefficients, and thermal diffusion factors for eight binary gas mixtures: He + SF6, He + CO2, He + O-2, He + N2O, CH4 + SF6, CH4 + CO2, CH4 + O-2, and CH4 +N2O were determined from the extended law of corresponding states for viscosity using the inversion technique for the corresponding interaction potential energies. Lennard-Jones (12-6), (LJ (12-6)), potential function is used as the initial model potential required by the technique. The interaction potential energies from this inversion technique reproduce the viscosities within 1%, the diffusion coefficients within 5%, and the thermal diffusion factors within 25%. The interaction potential energy determined from this inversion method for He + SF6 system is compared with other methods.