Surface tensions at the temperatures of (283.15, 288.15, 293.15, 298.15, 303.15, 308.15, and 313.15) K and isothermal (vapour + liquid) equilibrium at the temperatures of (288.15, 298.15, and 308.15) K of n-hexane with 1-chlorobutane or 1-chloropentane mixtures have been measured. Surface tension measurements were carried out with a drop volume tensiometer while the (vapour + liquid) equilibrium was obtained using an all-glass dynamic recirculating type still. Several bulk thermodynamic properties of the studied mixtures have been used together with the experimental measurements to analyse the results. Furthermore, a thermodynamic study of surface formation, including interesting properties such as excess surface compositions and excess properties of surface formation, is also presented. (C) 2008 Elsevier Ltd. All rights reserved.