Enthalpy of vaporization measurements by calorimetric techniques

Enthalpies of vaporization, \( \Delta _{\text{vap}} H^{\circ }_{298} \), were determined for perfluorooctyl-1-bromide (PFOB) at the temperature 298.15 K. Measurements were performed on an adiabatic vaporization calorimeter for the first time. Saturated vapor pressures are determined for PFOB by an ebulliometry method in the temperature range from 329 to 414 K. A second-order group additivity method has been applied to predict the vaporization enthalpies of some perfluorocompounds. The contributions of methyl, isopropyl, octyl and bromo group to the vaporization enthalpies of the perfluorocarbons derivatives are estimated and aimed at either prediction of properties of fluids.