212 new data points for solubility and density have been measured in the mixed,solvent electrolytic CO2-NaHCO3-Na2CO3-monoethylene glycol (MEG)-water system. Measurements were conducted at 2-60 degrees C at atmospheric pressure. An overview of methods available for determining the carbon dioxide and sodium content is given and the reverse Schreinemakers method was chosen. The method gives the amounts of all the species in the liquid. The solutions have a tendency to form metastable mixtures from which sodium carbonate salt hydrates may precipitate. Thirty metastable data points are reported.