Hi,
I have been using GSS and SpecE8 to calculate activity coefficients and perform concentration unit conversions in brine solutions with extremely high ionic strength. I have noticed that when converting between g/kg (ppt) to mol/l, the converted values are off by 1-2 moles compared to values obtained by doing 'long-hand' calculations using density measurements. Also, I am interested in activity of H2O, and this parameter is drastically lower when calculated with SpecE8 than when measured using a calibrated relative humidity meter.
I have loaded the thermo dataset thermo_hmw, which should employ Pitzer equations for calculations at high ionic strength, and have been applied previously to solutions analogous to mine. I was wondering whether I have made some error or whether I am outside the usability of the hmw dataset in the GWB Student edition.
An example dataset:
raw data in g/kg:
Mg++ 75.44
Na+ 0.3047
K+ 1.097
SO4-- 102.9
Cl- 119.3
density: 1.227 g/cm^3