PHASES

This keyword data block is used to define a name, chemical reaction, log K, and temperature dependence of log K for each gas component and mineral that is used for speciation, batch-reaction, transport, or inverse-modeling calculations. Normally, this data block is included in the database file and only additions and modifications are included in the input file.

Annotation (Details)

Keyword Explanation
Phase NameAlphanumeric name of phase, no spaces are allowed.
ReactionDissolution reaction for the phase to aqueous species. Any aqueous species, including e-, may be used in the dissolution reaction. The chemical formula for the defined phase must be the first chemical formula on the left-hand side of the equation. The dissolution reaction must precede any identifiers related to the phase. The stoichiometric coefficient for the phase in the chemical reaction must be 1.0.
log Klog K at 25 C for the reaction. Log K must be 0.0 for primary master species.
ΔHEnthalpy of reaction at 25 C for the reaction.
UnitsUnits for ΔH.
A1 - A5Parameters used in the analytical expression that defines log K as a function of temperature, e.g. log10K = A1 + A2*T + A3/T + A4*log10T + A5/T2, where T is in Kelvin.

Phases

Phase name Reaction log K ΔH Units A1 A2 A3 A4 A5 Database Reference Note
Aragonite CaCO3 = CO3-2 + Ca+2 -8.336 -2.589 kcal -171.9773 -0.077993 2903.293 71.595 0.0 Phreeqc_default Phreeqc
Dolomite CaMg(CO3)2 = Ca+2 + Mg+2 + 2 CO3-2 -17.09 -9.436 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Siderite FeCO3 = Fe+2 + CO3-2 -10.89 -2.48 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Rhodochrosite MnCO3 = Mn+2 + CO3-2 -11.13 -1.43 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Strontianite SrCO3 = Sr+2 + CO3-2 -9.271 -0.4 kcal 155.0305 0.0 -7239.594 -56.58638 0.0 Phreeqc_default Phreeqc
Witherite BaCO3 = Ba+2 + CO3-2 -8.562 0.703 kcal 607.642 0.121098 -20011.25 -236.4948 0.0 Phreeqc_default Phreeqc
Gypsum CaSO4:2H2O = Ca+2 + SO4-2 + 2 H2O -4.58 -0.109 kcal 93.7 0.00599 -4000.0 -35.019 0.0 Phreeqc_default Phreeqc # Appelo, submitted # 172.18 / 2.33 (Vm H2O = 13.9 cm3/mol)
Anhydrite CaSO4 = Ca+2 + SO4-2 -4.36 -1.71 kcal 84.9 0.0 -3135.12 -31.79 0.0 Phreeqc_default Phreeqc # 50 - 160oC, 1 - 1e3 atm, anhydrite dissolution, Blount and Dickson, 1973, Am. Mineral. 58, 323. # 136.14 / 2.95
Celestite SrSO4 = Sr+2 + SO4-2 -6.63 -4.037 kJ/mol -7.14 0.00611 75.0 0.0 0.0 Phreeqc_default Phreeqc # Howell et al., 1992, JCED 37, 464.
Barite BaSO4 = Ba+2 + SO4-2 -9.97 6.35 kcal -282.43 -0.08972 5822.0 113.08 0.0 Phreeqc_default Phreeqc # Blount 1977; Templeton, 1960
Hydroxyapatite Ca5(PO4)3OH + 4 H+ = H2O + 3 HPO4-2 + 5 Ca+2 -3.421 -36.155 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Fluorite CaF2 = Ca+2 + 2 F- -10.6 4.69 kcal 66.348 0.0 -4298.2 -25.271 0.0 Phreeqc_default Phreeqc
Quartz SiO2 + 2 H2O = H4SiO4 -3.98 5.99 kcal 0.41 0.0 -1309.0 0.0 0.0 Phreeqc_default Phreeqc
Al(OH)3(a) Al(OH)3 + 3 H+ = Al+3 + 3 H2O 10.8 -26.5 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Kaolinite Al2Si2O5(OH)4 + 6 H+ = H2O + 2 H4SiO4 + 2 Al+3 7.435 -35.3 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Albite NaAlSi3O8 + 8 H2O = Na+ + Al(OH)4- + 3 H4SiO4 -18.002 25.896 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Anorthite CaAl2Si2O8 + 8 H2O = Ca+2 + 2 Al(OH)4- + 2 H4SiO4 -19.714 11.58 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
K-feldspar KAlSi3O8 + 8 H2O = K+ + Al(OH)4- + 3 H4SiO4 -20.573 30.82 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
K-mica KAl3Si3O10(OH)2 + 10 H+ = K+ + 3 Al+3 + 3 H4SiO4 12.703 -59.376 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Chlorite(14A) Mg5Al2Si3O10(OH)8 + 16H+ = 5Mg+2 + 2Al+3 + 3H4SiO4 + 6H2O 68.38 -151.494 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Ca-Montmorillonite Ca0.165Al2.33Si3.67O10(OH)2 + 12 H2O = 0.165Ca+2 + 2.33 Al(OH)4- + 3.67 H4SiO4 + 2 H+ -45.027 58.373 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Talc Mg3Si4O10(OH)2 + 4 H2O + 6 H+ = 3 Mg+2 + 4 H4SiO4 21.399 -46.352 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Illite K0.6Mg0.25Al2.3Si3.5O10(OH)2 + 11.2H2O = 0.6K+ + 0.25Mg+2 + 2.3Al(OH)4- + 3.5H4SiO4 + 1.2H+ -40.267 54.684 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Chrysotile Mg3Si2O5(OH)4 + 6 H+ = H2O + 2 H4SiO4 + 3 Mg+2 32.2 -46.8 kcal 13.248 0.0 10217.1 -6.1894 0.0 Phreeqc_default Phreeqc # 277.11/2.60
Sepiolite(d) Mg2Si3O7.5OH:3H2O + 4 H+ + 0.5H2O = 2 Mg+2 + 3 H4SiO4 18.66 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Hematite Fe2O3 + 6 H+ = 2 Fe+3 + 3 H2O -4.008 -30.845 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Goethite FeOOH + 3 H+ = Fe+3 + 2 H2O -1.0 -14.48 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Fe(OH)3(a) Fe(OH)3 + 3 H+ = Fe+3 + 3 H2O 4.891 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Pyrite FeS2 + 2 H+ + 2 e- = Fe+2 + 2 HS- -18.479 11.3 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Mackinawite FeS + H+ = Fe+2 + HS- -4.648 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Sulfur S + 2H+ + 2e- = H2S 4.882 -9.5 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Vivianite Fe3(PO4)2:8H2O = 3 Fe+2 + 2 PO4-3 + 8 H2O -36.0 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Pyrolusite MnO2:H2O + 4 H+ + 2 e- = Mn+2 + 3 H2O 41.38 -65.11 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc # H2O added for surface calc's
Hausmannite Mn3O4 + 8 H+ + 2 e- = 3 Mn+2 + 4 H2O 61.03 -100.64 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Manganite MnOOH + 3 H+ + e- = Mn+2 + 2 H2O 25.34 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Pyrochroite Mn(OH)2 + 2 H+ = Mn+2 + 2 H2O 15.2 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Halite NaCl = Cl- + Na+ 1.57 1.37 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc #-analytic -713.4616 -.1201241 37302.21 262.4583 -2106915.
Sylvite KCl = K+ + Cl- 0.9 8.5 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc # -analytic 3.984 0.0 -919.55
CO2(g) CO2 = CO2 -1.468 -4.776 kJ/mol 10.5624 -0.023547 -3972.8 0.0 587460.0 Phreeqc_default Phreeqc # critical T, K # critical P, atm # acentric factor
Calcite CaCO3 = CO3-2 + Ca+2 -8.48 -2.297 kcal -171.9065 -0.077993 2839.319 71.595 0.0 Phreeqc_default Phreeqc # MW (100.09 g/mol) / rho (2.71 g/cm3)
SiO2(a) SiO2 + 2 H2O = H4SiO4 -2.71 3.34 kcal -0.26 0.0 -731.0 0.0 0.0 Phreeqc_default Phreeqc
Chalcedony SiO2 + 2 H2O = H4SiO4 -3.55 4.72 kcal -0.09 0.0 -1032.0 0.0 0.0 Phreeqc_default Phreeqc
Gibbsite Al(OH)3 + 3 H+ = Al+3 + 3 H2O 8.11 -22.8 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Sepiolite Mg2Si3O7.5OH:3H2O + 4 H+ + 0.5H2O = 2 Mg+2 + 3 H4SiO4 15.76 -10.7 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
FeS(ppt) FeS + H+ = Fe+2 + HS- -3.915 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
H2O(g) H2O = H2O 1.506 -44.03 kJ/mol -16.5066 -0.0020013 2710.7 3.7646 0.0 Phreeqc_default Phreeqc
O2(g) O2 = O2 -2.8983 0.0 kJ/mol -7.5001 0.0078981 0.0 0.0 200270.0 Phreeqc_default Phreeqc
H2(g) H2 = H2 -3.105 -4.184 kJ -9.3114 0.0046473 -49.335 1.4341 128150.0 Phreeqc_default Phreeqc
N2(g) N2 = N2 -3.1864 0.0 kJ/mol -58.453 0.001818 3199.0 17.909 -27460.0 Phreeqc_default Phreeqc
H2S(g) H2S = H+ + HS- -7.9759 0.0 kJ/mol -97.354 -0.031576 1828.5 37.44 28.56 Phreeqc_default Phreeqc
CH4(g) CH4 = CH4 -2.8 0.0 kJ/mol 10.44 -0.00765 -6669.0 0.0 1014000.0 Phreeqc_default Phreeqc # CH4 solubilities 25 - 100C
NH3(g) NH3 = NH3 1.7966 0.0 kJ/mol -18.758 0.0003367 2511.3 4.8619 39.192 Phreeqc_default Phreeqc
Oxg(g) Oxg = Oxg 0.0 0.0 kJ/mol -7.5001 0.0078981 0.0 0.0 200270.0 Phreeqc_default Phreeqc
Hdg(g) Hdg = Hdg 0.0 0.0 kJ/mol -9.3114 0.0046473 -49.335 1.4341 128150.0 Phreeqc_default Phreeqc
Ntg(g) Ntg = Ntg 0.0 0.0 kJ/mol -58.453 0.001818 3199.0 17.909 -27460.0 Phreeqc_default Phreeqc
Mtg(g) Mtg = Mtg -2.8 0.0 kJ/mol 10.44 -0.00765 -6669.0 0.0 1014000.0 Phreeqc_default Phreeqc # CH4 solubilities 25 - 100C
H2Sg(g) H2Sg = H+ + HSg- 0.0 0.0 kJ/mol -97.354 -0.031576 1828.5 37.44 28.56 Phreeqc_default Phreeqc
Melanterite FeSO4:7H2O = 7 H2O + Fe+2 + SO4-2 -2.209 4.91 kcal 1.447 -0.004153 0.0 0.0 -214949.0 Phreeqc_default Phreeqc
Alunite KAl3(SO4)2(OH)6 + 6 H+ = K+ + 3 Al+3 + 2 SO4-2 + 6H2O -1.4 -50.25 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Jarosite-K KFe3(SO4)2(OH)6 + 6 H+ = 3 Fe+3 + 6 H2O + K+ + 2 SO4-2 -9.21 -31.28 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Zn(OH)2(e) Zn(OH)2 + 2 H+ = Zn+2 + 2 H2O 11.5 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Smithsonite ZnCO3 = Zn+2 + CO3-2 -10.0 -4.36 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Sphalerite ZnS + H+ = Zn+2 + HS- -11.618 8.25 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Willemite Zn2SiO4 + 4H+ = 2Zn+2 + H4SiO4 15.33 -33.37 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Cd(OH)2 Cd(OH)2 + 2 H+ = Cd+2 + 2 H2O 13.65 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Otavite CdCO3 = Cd+2 + CO3-2 -12.1 -0.019 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
CdSiO3 CdSiO3 + H2O + 2H+ = Cd+2 + H4SiO4 9.06 -16.63 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
CdSO4 CdSO4 = Cd+2 + SO4-2 -0.1 -14.74 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Cerussite PbCO3 = Pb+2 + CO3-2 -13.13 4.86 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Anglesite PbSO4 = Pb+2 + SO4-2 -7.79 2.15 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Pb(OH)2 Pb(OH)2 + 2H+ = Pb+2 + 2H2O 8.15 -13.99 kcal 0.0 0.0 0.0 0.0 0.0 Phreeqc_default Phreeqc
Metacinnabar HgS + H+ = Hg+2 + HS- -36.8 51.11 kcal 0.0 0.0 0.0 0.0 0.0 Aquamer_default DR13 # [DR13]
Cinnabar HgS + H+ = Hg+2 + HS- -37.6 49.65 kcal 0.0 0.0 0.0 0.0 0.0 Aquamer_default DR13 # [DR13]
HgO(s) HgO + 2H+ = Hg+2 + H2O 2.37 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Aquamer_default PO05 # [PO05]
HgCO3:2HgO(s) HgCO3:2HgO + 4H+ = 3Hg+2 + 2H2O + CO3-2 -11.491 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Aquamer_default PO05 # [PO05]
Hg3(PO4)2(s) Hg3(PO4)2 = 3Hg+2 + 2 PO4-3 -49.27 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Aquamer_default PO05 # [PO05]
(HgOH)3PO4(s) (HgOH)3PO4 + 3H+ = 3Hg+2 + PO4-3 + 3H2O -21.738 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Aquamer_default PO05 # [PO05]
HgHPO4(s) HgHPO4 = Hg+2 + PO4-3 + H+ -25.438 0.0 kJ/mol 0.0 0.0 0.0 0.0 0.0 Aquamer_default PO05 # [PO05]


References

RefID Reference
Phreeqc https://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/index.html
DR13 Drott, A., Björn, E., Bouchet, S. and Skyllberg, U. (2013) Refining Thermodynamic Constants for Mercury(II)-Sulfides in Equilibrium with Metacinnabar at Sub-Micromolar Aqueous Sulfide Concentrations. Environ. Sci. Technol. 47, 4197-4203.
PO05 Powell, K.J., Brown, P.L., Byrne, R.H., Gajda, T., Hefter, G., Sjoberg, S. and Wanner, H. (2005) Chemical speciation of environmentally significant heavy metals with inorganic ligands - Part 1: The Hg2+-Cl-, OH-, CO32-, SO42-, and PO43- aqueous systems - (IUPAC technical report). Pure Appl. Chem. 77, 739-800.