HEAT-CAPACITY CORRECTIONS TO A STANDARD STATE - A COMPARISON OF NEW AND SOME LITERATURE METHODS FOR ORGANIC LIQUIDS AND SOLIDS

The estimation methods commonly used to correct phase change enthalpie s to the standard state are compared where possible to experimental me asurements. Heat capacity corrections for liquid-gas equilibria are fo und to correlate with molecular structure, and we suggest an improved method for estimating these corrections using group methods. A similar improvement for estimating heat capacity corrections for solid-gas eq uilibria using group methods is also proposed. Heat capacity correctio ns for liquid-solid equilibria are examined. These corrections were fo und to be comparable in magnitude to the experimental error associated with heat capacity measurements, so it was not possible to obtain any meaningful correlations.