Excess molar volumes and excess isentropic compressibilities of 2-pyrrolidinone at 308.15Â K

Molar excess volumes VijkE and speeds of sound, uijk of 2-pyrrolidinone (i) + benzene (j) + toluene or o- or p-xylene (k) ternary mixtures have been measured as a function of composition at 308.15 K. The observed speeds of sound data have been utilized to calculate their excess isentropic compressibilities. The observed data have been fitted to Redlich-Kister equation to calculate ternary adjustable parameters and standard deviations. Molar excess volumes, VijkE and excess isentropic compressibilities, (κSE)ijk data for the investigated mixtures have been analyzed in terms of Graph theory and Flory theory. It has been observed that VijkE and (κSE)ijk values calculated by Graph theory compare well with their corresponding experimental values.