title: A contribution to the debate about hydrophobic effects.
abstract: Based on available measurements of the concentration dependence of the volume and the heat capacity of aqueous solutions of low molecular weight compounds it is suggested that non-polar molecules or non-polar groups in aqueous solution fluctuate between solvated and non-solvated states. The experimental data indicate that the change in standard free energy of the hydrophobic solvation is positive and so large that the solvation is incomplete even in the most dilute solutions studied. It is tentatively suggested that the hydrophobic solvation enhances the solubility in water of non-polar substances, and that the reason why non-polar groups in protein solutions are buried in the interior of the protein conformations is a low degree of solvation of these groups in the solvent exposed state.
mesh_terms: D008433:Mathematics; D008970:Molecular Weight; D011506:Proteins; D012996:Solutions; D013816:Thermodynamics; D014867:Water
chemical_list: D011506:Proteins; D012996:Solutions; D014867:Water