Solubility of 13 Nonpolar Gases in Deuterium Oxide at 15–45°C and 101.325 kPa. Thermodynamics of Transfer of Nonpolar Gases from Hsub2/subO to Dsub2/subO

Using a computer controlled version of the Ben-Naim and Baer apparatus, the solubilities of He, Ne, Ar, Kr, H ₂ , D ₂ , N ₂ , O ₂ , CH ₄ , C ₂ H ₆ , C ₃ H ₈ , CF ₄ , and SF ₆ in D ₂ O (and the solubility of CF ₄ in H ₂ O) were determined at four temperatures in the range 288 to 318 K and at a partial pressure of gas of 101.325 kPa. The precision of the measurements was 0.3–1.0%. The experimental data were processed using rigorous thermodynamic methods and were fitted to the Clarke-Glew-Weiss equation. Changes in the thermodynamic properties on solution were calculated from the smoothing equations. Scaled-particle theory (SPT) was used to determine the Lennard-Jones (6,12) pair potential parameters for D ₂ O: σ=0.275 nm and ε/k=83.4 K. Experimental mole fraction solubilities and thermodynamic functions at 298.15 K were compared with results calculated using the SPT. The thermodynamic transfer functions of gases from H ₂ O to D ₂ O were calculated. The changes induced by the solvation process on the structure of water were estimated from the Gibbs energy of transfer and the difference in the hydrogen bond energies for D ₂ O and H ₂ O.