CALCULATION OF CARBON-DIOXIDE EQUILIBRIUM BY PITZER METHOD

The calculations of carbon dioxide equilibrium for seawater model systems were carried out for the temperature 25-degrees-C and salinity 0-100 parts-per-thousand by Pitzer's method. The results are compared with the data received by standard method of calculation using stoichimetric acidity constants. Basing on established agreement of different calculative methods, recommendation on selection of approximating equations for calculation of stoichimetric dissociative constants of carbonic and boric acids in the salinity range 0-100 parts-per-thousand are suggested. The value of association Ca2+-CO3(2-) ion - pair constant proposed equals to K(CaCO30) = 4.30.