Refractive index and related properties for the mixture (1, 4-dioxane + water) at temperature T= (295.15, 298.15, 301.15, 304.15, 307.15, 310.15 and 313.15) K

The refractive index ${n_D}$nD for the mixture (1,4-dioxane (1) + water (2)) was measured over the whole composition range at different temperatures and atmospheric pressure. From measured values of the refractive indices, the molar refraction ${R_m}$Rm, reduced molar free volumes ${{{V_m}} \over {{R_m}}}$VmRm, molecular radii $r$r and internal pressure, ${P_{int}}$Pint were calculated. On the other hand, some excess parameters were also deduced. The obtained results have been discussed and interpreted in terms of the type and nature of specific intermolecular interactions existed between the components. Furthermore, we have used nine mixing rules for refractive index proposed by different authors to calculate the refractive indices of the present mixture. A comparative study was carried out between the measured and calculated indices. The Redlich-Kister polynomial equation has been used to fit the presented excess parameters to derive the adjustable fitting coefficients and estimate the standard error values.