The partitioning of a neutral solute between two liquid phases is important for a range of industrial, environmental, and biological processes. The resulting partition coefficient is of great fundamental significance as it can both readily be measured and can be related to the underlying intermolecular interactions. During its measurement, it is desired to keep the solute concentration dilute (less than 0.01 M) in each phase so that the solute may be assumed infinitely dilute . In doing so, the partition coefficient of a solute between two liquid phases at equilibrium (I and II, P I/II 1 ) may be computed as :