Critical asymmetry of liquid–liquid coexistence curve of binary mixture nitromethane + 3-pentanol

Abstract The liquid–liquid coexistence curves and the isobaric heat capacities per unit volume of the binary solution {nitromethane + 3-pentanol} have been measured in a wide temperature range. The values of the critical exponents were derived and found to be in good agreements with the theoretical ones of the 3D-Ising universality. It was found that the asymmetric behavior of the diameter of the coexistence curve was well described by the complete scaling theory with the consideration of the heat capacity related term. Moreover, analysis of the asymmetric behavior of the diameters of coexistence curves showed an unusual large asymmetric coefficient indicating the compressibility of this solution was not negligible, which was significantly different from that of {polar + nonpolar} binary solutions we investigated previously.