Excess molar enthalpies and excess molar volumes of (water+octan-1-OL or +octan-2-OL) at 298.15 K

The excess molar enthalpies and volumes have been determined for the binary system (water+octan-1-ol or +octan-2-ol) by means of direct calorimetric a nd densimetric measurements in the miscibility range. The experimental data were described through a Redlich-Kister type equation. For excess enthalpi es a sigmoidal shape is predicted, while excess volumes are negative except for a little positive queue observed for (water+octan-1-ol) system at very low water content. Also the partial molar enthalpies of solution and the p artial molar volumes of water in the two isomeric octanols at infinite dilu tion have been evaluated and discussed. A comparison is made between excess enthalpies and excess free energies calculated by the UNIFAC method.