Interfacial free energy and the hydrophobic effect.

Interfacial free energies demonstrate clearly that the antipathy between hydrocarbon and water rests on the strong attraction of water for itself. However, the unfavorable free energy associated with this antipathy, per unit area of contact between bulk hydrocarbon and water, is about 3-fold larger than a similar figure derived from solubility data per unit area of contact between a single dissolved hydrocarbon molecule and water. The discrepancy illustrates the difficulty in applying macroscopic concepts such as "interfacial surface" at the molecular level and can be formally resolved, at least qualitatively, by the predicted effect of surface curvature on surface tension.