Qin et al. measured the distribution of methane and carbon dioxide between liquid and vapor in the H2O, CO2 and CH4 ternary system up to 100⁰C and 400 bar. Aqueous and gas phases were equilibrated between 8-36 h at the desired pressure and temperature. Gas and liquid samples were obtained upon equilibration. The volume of CH4 emerging from the aqueous samples was measured and converted to moles using the ideal gas law. The dissolved CO2 was completely converted to HCO 3 -and CO 3 -2 by NaOH titrations, which were then quantified by coulometric titrations. Figure shows the experimental and modelled solubility of CO2 (panels a and c) and CH4 (panels b and d) from the CO2-CH4 binary gas mixture in water represented as a function of the CO2/CH4 partial pressure upon equilibration.