When a hydrophobe is dropped in an aqueous medium, hydrogen bonds between water molecules will be broken to make room for the hydrophobe; however, water molecules do not react with hydrophobe. This is considered an endothermic reaction, because when bonds are broken heat is put into the system. The hydrophobic effect is considered to be the major driving force for the folding of globular proteins. It results in the burial of the hydrophobic residues in the core of the protein. It is exemplified by the fact that oil and water do not mix and was described well by G. S. Hartley in 1936. 1 Hydrophobic effect. The hydrophobic effect increases the thermodynamic activity of large hydrophobic molecules of metal complexes formed in the aqueous phase of solvent extraction systems, which promotes their transfer from the aqueous to the organic phase.
