How it works

• If the chemical formula or name of the mineral introduced is in the database, the system will calculate its corresponding exergy and will show the standard Gibbs free energy and Enthalpy value with which the chemical exergy has been calculated.
• If the system does not recognize the chemical formula introduced, it is still able to calculate its exergy once you enter its specific Gibbs free energy.
• The given exergy is calculated with Eq.1 with the chemical exergy of the elements shown in Table 1, from the latest Reference Environment defined by Szargut et. al. 2005
• The Gibbs free energy values are taken from Faure 1991, which is a compilation of the following sources: Woods and Garrels (1987), Weast et al. (1986), Drever (1982), Brookins (1988) , Lindsay (1979) , Krauskopf (1979) , Garrels and Christ (1965) and Tardy and Garrels (1974).

How to enter the chemical formula

1. 1. The program will only recognize numbers and letters belonging to chemical elements. No special characters such as “-”; “+”; “.” are allowed:
   • You should write “Ag” for: “Ag+”; Ag+2”; “Ag (c)”; The output will show you all possible substances with compound formula “Ag”
   • Compound “NaAlSi2O6.2H2O” should be rewritten as: “NaAlSi2O6(H2O)2”
2. 2. The program is sensible to upper and lower case letters:
   • "Co" is Cobalt, while "CO" is Carbon Monoxide
3. 3. The program recognizes only parenthesis “( )”, do not include any square brackets “[ ]” or accolades “{ }”