Estimation of Heat Capacity of Boiling of Organic Compounds

The aim of this study is to develop a widely applicable model for predicting the heat-capacity change associated with boiling at atmospheric pressure ((delta)Cpb) of organic compounds. A semiempirical model is generated utilizing a flexibility index (tau) and a hydrogen-bonding parameter. This model is based upon experimental apparent (delta)Cpb values of 619 organic compounds. The average absolute error for the estimation is 7.1 J/K mol. The proposed model quantitatively establishes the impact of flexibility and hydrogen bonding on the apparent (delta)Cpb. It is shown to be more accurate when compared to some of the previously described methods.