MODIFIED TROUTONS-RULE FOR PREDICTING THE ENTROPY OF BOILING

Simple modifications of Trouton's rule for estimating the entropy of b oiling of organic compounds are presented. An empirical equation is de veloped which expresses the entropy of boiling as a function of molecu lar flexibility and hydrogen bonding. This equation, which enables the simple yet reasonable estimate of entropy of boiling directly from mo lecular structure, was generated from a training set of 850 structural ly diverse compounds. The average absolute percent error for a test se t of 88 compounds is 2.5% which is more accurate than Trouton's rule.