The density, rho(ijk) and speed of sound, u(ijk) of ternary {1-ethyl-3-methylimidazolium tetrafluoroborate (i) + pyrrolidin-2-one} or {1-methyl pyrrolidin-2-one (j) + cyclopentanone or cyclohexanone (k)} mixtures have been measured at temperatures (293.15, 298.15, 303.15, 308.15) K. The excess molar volume, V-ijk(E) and excess isentropic compressibility, (kappa(E)(S))(ijk) (obtained by employing density and speed of sound data) have been fitted to Redlich-Kister equation to determine ternary adjustable parameters along with their standard deviations. The V-ijk(E) and (kappa(E)(S))(ijk) results have been tested in terms of Graph and Prigogine-Flory-Patterson (PFP) theories. The results indicate that V-ijk(E) and (kappa(E)(S))(ijk) values calculated by Graph theory are comparable to the experimental values. (C) 2015 Elsevier Ltd. All rights reserved.