where ∆G Transfer is the transfer free energy of a solute from the pure aqueous phase to toluene. R is the gas constant and T is the temperature. ∆G solv w and ∆G solv tol are the solvation free energies of a solute in water and toluene, respectively. For all calculations, the temperature of 25 °C and the reference state of 1 mol/L in the liquid and the gas is used.