Accurate (p, ρ, T) data for two new (carbon dioxide + nitrogen) mixtures from (250 to 400) K at pressures up to 20 MPa

► New (p, ρ, T) data of two mixtures of nitrogen and carbon dioxide are reported. ► Experimental data show a disagreement with the equation of state at low temperatures and high pressures. ► Relative deviations in density increase with the carbon dioxide molar fraction of the mixture. ► Only relative deviations at pressures below 10 MPa are within a 0.1% band.