Experimental bubble pressure, as well as liquid density of (CO2 + NO2/N2O4) mixtures are reported at temperatures ranging from (298 to 328.45) K. Experiments were carried out using a SITEC high-pressure variable volume cell. Transition pressures were obtained by the synthetic method and liquid density was deduced from measurement of the cell volume. Correlation of experimental results was carried out without considering chemical equilibrium of NO2/N2O4 system. (Liquid + vapour) equilibrium was found to be accurately modelled using the Peng-Robinson equation of state with classical quadratic mixing rules and with a binary interaction coefficient k(ij) equal to zero. Nevertheless, modelling of liquid density values was unsatisfactory with this approach. (C) 2011 Elsevier Ltd. All rights reserved.