Excess molar volumes V-E excess molar enthalpies H-E speeds of sound, u and vapour-liquid equilibrium data of 1 3-dioxolane (1) + aniline or N-methyl aniline or o-toluidine (j) binary mixtures have been measured as a function of composition at 308 15 K Speeds of sound and vapour-liquid equilibrium data of (I + J) binary mixtures have been utilized to determine isentropic compressibilities changes of mixing id and excess Gibbs free energy G(E) The observed data have been analyzed in term of Graph theory which involves the topology of the mixture constituents It has been observed V-E H-E K-S(E) and G(E) values predicted by Graph theory compare well with their corresponding experimental values (C) 2010 Elsevier B V All rights reserved