Thermodynamic constants

Calculate the thermodynamic constants in sea water. The calculated constants are on the SWS pH scale. The thermodynamic constants are calculated in mmol/kg (mmol/l). This script uses the formulas from MILERO (GCA, 1995) and CLEGG AND WHITFIELD (GCA, 1995), with corrections for the pressure from MILERO (1983, CHEM. OCEAN v. 8), and UNESCO (1983). The original FORTRAN code has been written by B.P. BOUDREAU (COMPUTERS & GEOSCIENCES, 1996) for the numerical diagenetic model CANDI.

Enter values for T, S, P to calculate thermodynamic constants of sea water under those conditions:

Parameter	Unit	Range	User-input
Temperature	°C	0-40
Salinity	PSU (ppt)	0.5-43
Pressure	atm (1 atm at surface)	0-1200

dissociation constant of H₂O
1st dissociation constant of CO₂(aq)
2nd dissociation constant of CO₂(aq)
dissociation constant of B(OH)₃
1st dissociation constant of H₃PO₄
2nd dissociation constant of H₃PO₄
3rd dissociation constant of H₃PO₄
dissociation constant of HNO₃
dissociation constant of NH₄
1st dissociation constant of H₂S
solubility product of CaCO₃ (Aragonite)
solubility product of CaCO₃ (Calcite)

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