Refractive Indices and Surface Tensions of Binary Mixtures of Isoamyl Acetate, Ethyl Caproate, Ethyl Benzoate, Isoamyl Butyrate, Ethyl Phenylacetate, and Ethyl Caprylate with Ethanol at (288.15, 298.15, 308.15, and 318.15) K

Abstract

Refractive indices and surface tensions for six binary mixtures formed by the flavor esters (isoamyl acetate, ethyl caproate, ethyl benzoate, isoamyl butyrate, ethyl phenylacetate, and ethyl caprylate) with ethanol over the whole composition range were measured at four different temperatures (288.15, 298.15, 308.15, and 318.15) K and atmospheric pressure. Refractive indices were measured using a digital Abbe-type refractometer. Surface tensions were determined using the Wilhelmy-plate method. From experimental data, deviations in the refractive index Δ n were calculated both on a mole fraction basis and on a volume fraction basis. The deviations in the molar refraction Δ R and the deviations in the surface tension Δ σ were calculated on a mole fraction basis. The binary data of these deviations were correlated as a function of the mole fraction using the Redlich−Kister equation.