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Diss Factsheets

Administrative data

water solubility
Type of information:
calculation (if not (Q)SAR)
Migrated phrase: estimated by calculation
Adequacy of study:
key study
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
The Facility for the Analysis of the Chemical Thermodynamics (FACT, is a thermochemical database for calculations in chemical metallurgy which has been developed by the École Polytechnique de Montreal and McGill University in Canada since 1976. This Database has been recommended in the ECHA guidance on information requirements and chemical safety assessment (Chapter R.7a) to estimate the solubility of sparingly soluble metal compounds.

Data source

Reference Type:
other: Database
Facility for Analysis of Chemical Thermodynamics (FACT)
École Polytechnique de Montreal and McGill University in Canada
Bibliographic source:

Materials and methods

Principles of method if other than guideline:
The FACT database for the calculation of the aqueous solution equilibrium evaluates and optimizes data from the primary literature by incorporating various solution models (Margules polynomials, Unified Interaction Parameter Formalism, Quasi-chemical model, Sub-lattice models, Pitzer parameters, etc).
GLP compliance:
Not applicable for modelled data
Type of method:
other: Modelled data

Test material

Constituent 1
Chemical structure
Reference substance name:
EC Number:
EC Name:
Cas Number:
Molecular formula:

Results and discussion

Water solubility
Water solubility:
0.002 mg/L
25 °C
ca. 8.9
Details on results:
1 mol of cerium metal dissolved in 55.5 mol (= 1 kg) water releases approx. 2 mol ideal gas H2, 55.5 mol liquid H2O and 1 mol CeO2 solid. Ce metal is therefore poorly soluble, being Ce3+ the only specie released into the water phase that may be of relevance. Knowing that the MW = 140,12 and that 1kg H2O = 1L, the saturation mass concentration of Ce in solution is 1.5552E-08 mol/L (= 2,1794E-03 mg /L)

Any other information on results incl. tables

FACT Format

 55.508 H2O + Ce =


  2.0639    mol  gas_ideal

  (5.1959 gram, 2.0639 mol, 50.626 litre, 1.0263E-04 g/ml)

          (298.15 K, 1 atm,    a=1.0000)

          ( 0.96865        H2

          + 3.1352E-02     H2O

          + 2.3864E-36     H

          + 2.8059E-48     OH

          + 2.4287E-65     HOOH

          + 1.3218E-73     CeO3H3)


 + 53.444    mol  aqueous

  (962.80 gram, 53.444 mol)

          (298.15 K, 1 atm,    a=1.0000)

          ( 55.508         H2O_liquid

          + 8.2212E-04     H2

          + 7.7706E-06     OH[-]

          + 2.5898E-06     Ce[3+]                                 T

          + 1.2718E-09     H[+]

          + 1.1327E-44     Ce[4+]                                 T

          + 2.4700E-60     HOOH

          + 3.9067E-63     HO2[-])

          (Eh=-0.526 V, pH= 8.896)


 + 1.0000    mol  CeO2_solid

  (172.11 gram, 1.0000 mol)

          (298.15 K, 1 atm, S1, a=1.0000)


 + 0.00000   mol  H2O_ice                                         T

          (298.15 K, 1 atm, S1, a=0.78721)


 + 0.00000   mol  Ce6O11_solid

          (298.15 K, 1 atm, S1, a=1.6838E-11)


 + 0.00000   mol  Ce2O3_solid

          (298.15 K, 1 atm, S1, a=1.0748E-19)


 + 0.00000   mol  Ce18O31_solid

          (298.15 K, 1 atm, S1, a=7.9859E-57)


 + 0.00000   mol  CeH2_solid

          (298.15 K, 1 atm, S1, a=3.8254E-69)


 The cutoff concentration has been specified to 1.0000E-75


 Data on 3 product species identified with "T" have been extrapolated



      H           G           V           S          Cp

     (J)         (J)       (litre)      (J/K)       (J/K)


 -1.63813E+07 -1.75967E+07 5.06265E+01 4.07644E+03 4.32481E+03


 Total mass/gram = 1140.1

 Total mass/gram excluding gas = 1134.9


ChemSage Format

 T = 298.15 K

 P = 1.00000E+00 atm

 V = 5.06265E+01 dm3



 H2O                       5.5508E+01

 Ce                        1.0000E+00


                          EQUIL AMOUNT MOLE FRACTION    FUGACITY

 PHASE: gas_ideal             mol                          atm

 H2                        1.9992E+00    9.6865E-01    9.6865E-01

 H2O                       6.4707E-02    3.1352E-02    3.1352E-02

 H                         4.9253E-36    2.3864E-36    2.3864E-36

 OH                        5.7911E-48    2.8059E-48    2.8059E-48

 HOOH                      5.0125E-65    2.4287E-65    2.4287E-65

 CeO3H3                    2.7281E-73    1.3218E-73    1.3218E-73

 TOTAL:                    2.0639E+00    1.0000E+00    1.0000E+00


PHASE: aqueous               mol         MOLALITY      ACTIVITY

 H2O_liquid                5.3443E+01    5.5508E+01    9.9999E-01

 H[+]                      1.2245E-09    1.2718E-09    1.2718E-09

 H2                        7.9153E-04    8.2212E-04    8.2212E-04

 O2                        NOT CALCD.    NOT CALCD.   <1.0000E-75

 OH[-]                     7.4815E-06    7.7706E-06    7.7706E-06

 HO2[-]                    3.7614E-63    3.9067E-63    3.9067E-63

 HOOH                      2.3781E-60    2.4700E-60    2.4700E-60

 Ce[3+]                  T 2.4934E-06    2.5898E-06    2.5898E-06

 Ce[4+]                  T 1.0905E-44    1.1327E-44    1.1327E-44

 TOTAL:                    5.3444E+01                   1.0000E+00


                             mol                        ACTIVITY

 CeO2_solid(s)             1.0000E+00                   1.0000E+00

 H2O_ice(s)              T 0.0000E+00                   7.8721E-01

 Ce6O11_solid(s)           0.0000E+00                   1.6838E-11

 Ce2O3_solid(s)            0.0000E+00                   1.0748E-19

 Ce18O31_solid(s)          0.0000E+00                   7.9859E-57

 CeH2_solid(s)             0.0000E+00                   3.8254E-69


  Cp_EQUIL      H_EQUIL      S_EQUIL      G_EQUIL      V_EQUIL

    J.K-1          J          J.K-1          J           dm3


 4.32481E+03 -1.63813E+07  4.07644E+03 -1.75967E+07  5.06265E+01




Properties for aqueous:

 pH = 8.8956

 Eh/V =-0.52602

 Total solute molality = 8.3248E-04

 Ionic strength = 1.5540E-05

 Osmotic coefficient = 1.0000


 Mole fraction of system components:

               gas_ideal   aqueous

 Ce            6.5071E-74  1.5552E-08

 O             1.5434E-02  0.33333

 H             0.98457     0.66667


 The cutoff limit for phase or gas constituent activities is 1.0000E-75


 Data on 3 constituents marked with 'T' are extrapolated outside their valid

 temperature range

Applicant's summary and conclusion

Interpretation of results (migrated information): insoluble (< 0.1 mg/L)
Cerium metal is insoluble in water at 25°C, 1 atm and pH= 8.89.
Executive summary:

The modelled FACT calculations here confirm the insolubility properties of cerium metal in water, as already known and widely published in other databases and handbooks of high reputation for the scientific community such as RTECS or the CRC Handbook of Chemistry and Physics, respectively.