“…The prediction of either entropy change, however, is another matter. A variety of quantities on which the entropy changes might depend have been proposed: DH ;pp b [7], the critical temperature and volume [8,9], the sum of atomic number [10], T b [11], molecular mass [11], molecular volume [12][13][14][15][16], symmetry number [17], number of torsions [17], the extent of planarity [17], or type of functional group [18]. None of these, though, have had a firm enough combination of simplicity, accuracy, and a sound theoretical basis to surpass Hildebrand's rule let alone Trouton's rule.…”