Dielectric and Pressure Virial Coefficients of Imperfect Gases. IV C2H4 and C2H4–Ar Mixtures

Results of measurements at 50°C for five mixtures and at 50, 100, and 150°C for pure ethylene are given. The pressure second virial coefficients of the mixtures are in reasonably good agreement with values predicted from combining rules and viscosity derived Lennard-Jones parameters for the pure gases. The dielectric coefficients of pure ethylene vary approximately inversely as the absolute temperature, in contrast to earlier results which showed an anomalous increase with temperature. Attributing the major contribution to dipole moments induced by ethylene quadrupole fields gives an average quadrupole moment for ethylene of 3.9 × 10−26 esu·cm2 from the pure gas data and 4.2 × 10−26 esu·cm2 from the mixture data, but it is not possible to derive values of the two independent moments from the results.