Densities, apparent molar volumes, and surface tension of aqueous 3-chloropropan-1-ol and 3-chloropropan-1,2-diol were determined at temperatures from (283.08 to 308.15) K. The results of the volumetric measurements have been used to calculate the following thermodynamic quantities at T = 298.15 K. For 3-chloropropan-1-ol(aq):
โข mol -1 . The preferential interaction parameters of the interaction of 3-chloropropan-1-ol and 3chloropropan-1,2-diol with two structurally homologous proteins (hen egg-white lysozyme and ฮฑ-lactalbumin) have been calculated by correlating the measured surface tension data to the surface areas of these proteins. The data on the measured apparent molar volumes and surface tension of aqueous 3-chloropropan-1-ol and 3-chloropropan-1,2-diol, in combination with the thermal denaturation data and surface area values of hen egg-white lysozyme from literature, clearly indicate a parallel trend in changes in the surface tension of water, partial molar volume, and ability to alter the thermal stability of these proteins.