As. Hyman et al., THE ENTROPY TERM IN ISODESMIC, ASSOCIATION, AND CONFORMATIONAL EQUILIBRATION REACTIONS, Structural chemistry, 5(6), 1994, pp. 399-401
Isodesmic reactions involving methyl, phenyl, and vinyl species are sh
own to be accompanied by small entropy changes. In contrast, the ''ass
ociation'' reaction of methane with vinyl species has a large entropy
change that is quite well estimated by approximate translational entro
py differences. The effect of neglecting multiple species on conformat
ional equilibrium returns us to small but still predictable changes.