Excess molar enthalpies of (2-butanone + cyclohexane, or methylcyclohexane, or toluene, or chlorobenzene, or cyclohexanone) and excess molar heat capacities of (2-butanone + benzene, or toluene, or chlorobenzene, or cyclohexanone) were measured at T = 298.15 K. Aliphatic systems were endothermic and the chlorobenzene system was exothermic. On the other hand, the toluene system changed sign to be S-shaped similar to the benzene system reported by Kiyohara et al. The values of excess molar enthalpies of the present mixtures were slightly larger than the corresponding mixtures of cyclohexanone already reported. Excess molar heat capacities of aromatic systems were characteristically S-shaped for the mixture containing aromatics. The values of the present mixtures were less than the corresponding mixtures of cyclohexanone. The mixture (2-butanone + cyclohexanone) was endothermic for H-m(E) and negative for C-p,m(E).