Densities, refractive indices, and viscosities were determined for two ionic liquids, 1-methyl-3-octylimidazolium tetrafluoroborate and 1-methyl-3-butylimidazolium perchlorate, and for their mixtures with ethanol at atmospheric pressure and temperatures from (278.15 to 363.15) K. The results for the pure components were correlated successfully by empirical equations. Excess molar volume, viscosity deviation, and refractive index deviation were calculated and correlated by the Redlich-Kister polynomial equation. As the numbers of parameters for Redlich-Kister polynomial equations are large, a model with one parameter was proposed to calculate densities, viscosities, and refractive indices of binary mixtures. On the basis of the proposed model, the physical properties of binary solutions are calculated from pure component physical properties, their mole fractions, and an adjustable parameter, which is determined by fitting of the experimental data. The results of the model represent reasonable accuracy for physical properties of binary systems.