A study of densities and volumetric properties of binary mixtures of N-methyl-2-pyrrolidone with xylene at different temperatures and atmospheric pressure

The densities of binary mixtures of N-methyl-2-pyrrolidone (NMP) with o-xylene, m-xylene, and p-xylene, including those of pure liquids, over the entire composition range were measured at T = (293.15, 303.15, 313.15, 323.15, 333.15, 343.15, and 353.15) K and atmospheric pressure. From the experimental data, the excess molar volume, VmE, and partial molar volumes, Vm,1 and Vm,2, were calculated over whole composition range. The VmE values were found negative for all the mixtures at each temperature studied, and decrease with rising temperature. The extent of negative deviations in VmE values follows the order: p-xylene > m-xylene > o-xylene. The variation of these parameters with composition and temperature of the mixtures has been discussed.