Excess molar volumes V-E excess molar enthalpies H-E and speeds of sound u data of {tetrahydropyran (1) + benzene or toluene or o- or p or m xylene (j)} binary mixtures have been measured as a function of composition at a temperature of 308 15 K Speeds of sound data have been utilized to predict excess isentropic compressibilities lambda(E)(S) V-E H-E and lambda(E)(S) data for the investigated mixtures have been analyzed in terms of the Graph theory which in turn deals with topology of the constituents of mixtures An analysis of V-E data in terms of Graph theory suggests that these mixtures are characterized by interactions between dipole of tetrahydropyran and pi-electron cloud of aromatic ring of aromatic hydrocarbons to form 1 1 molecular complex It has been observed that V-E H-E and lambda(E)(S) values predicted by the Graph theory compare well with their corresponding experimental values (C) 2010 Elsevier Ltd All rights reserved