Excess enthalpies and excess volumes of [xCO2+(1 –x)N2O] in the liquid and supercritical regions

Abstract

Measurements of the excess molar enthalpy, H^E_m, and excess molar volume, V^E_m, of [xCO₂+(1 –x)N₂O] are described. The measurements are in both the liquid and supercritical regions and cover the range 262.4–324.7 K at pressures up to 12.08 MPa. The excess functions at 262.4 K are small, but in the critical region very large H^E_m and V^E_m were measured. The uncertainty of the H^E_m values is ±2.5% and that of the V^E_m is ±4%. The Patel–Teja equation of state reproduces all the main features of H^E_m(x) and V^E_m(x), and has been used to generate H^E_m(p, x) and V^E_m(p, x) surfaces at 312.5 K.