Densities and refractive indices have been measured for binary mixtures of 1-propyronitrile-3-hexylimidazolium bromide + ethanol in the temperature range 293.15-323.15 K. From the experimental data the excess molar volume V E, refractive index deviation �n D, and the coefficient of thermal expansion α were calculated and fitted to fifth- and third-order Redlich-Kister type equations, respectively. Using the measured densities, the apparent molar volumes (V Φ), limiting apparent molar volumes (V Φ o) and limiting apparent molar expansivities (E Φ o) were also determined and the details are discussed. © Springer Science+Business Media, LLC 2011.