The densities of (1-pentanol + cyclohexane or benzene) have been measured at 15 K intervals from T= 283.15 K to T= 328.15 K for comparison with the results of (2-ethoxyethanol + cyclohexane or benzene). The excess volumes V E , excess thermal expansivities α E , and the pressure derivatives of the excess enthalpies (∂H E /∂P) T , were estimated from the measured densities. The values of V E and their temperature dependence for the 1-pentanol systems were found to be positive over the entire concentration range. The behaviour of α E for (1-pentanol + cyclohexane) is quite different from that of (2-ethoxyethanol + cyclohexane), while the α E value for (1-pentanol + benzene) is very similar to that of (2-ethoxyethanol + benzene). The behaviour of these thermodynamic properties are discussed in terms of inter- and intra-molecular hydrogen bonds and π electrons.