Ferrihydrite(2L)

Formula : Fe(OH)3

Family: 
Hydroxides
Space group: 
Trigonal - Hexagonal Scalenohedral HM symbol (-3 2/m) Space Group: P 31c
Dana class: 
4.3.2.2III - 4 Oxide Minerals ; 4.3 Simple Oxides with a cation charge of 3+ (A+++2 O3) ; 4.3.2

Dernière mise à jour le 25.01.2021

THERMODYNAMICS

Individual properties (298.15 K)
M
g·mol-1
 V°
cm3·mol-1
 ΔGºf
J·mol-1
 ΔHºf
J·mol-1
 Sº
J·mol-1·k-1
 CP
J·mol-1·K-1
106.869 34.360 (Ref.: 92wol) Wolery T.J., 1992. EQ3/6: A software Package for Geochemical Modelling of Aqueous Systems: Package Overview and Installation Guide. Technical Report UCRL-MA-110662 PT I ed., Lawrence Livermore National Laboratory (USA). -708294 (Ref.: 04maj/nav) Majzlan, J., Navrotsky, A., Schwertmann, U. (2004) Thermodynamics of iron oxides: Part III. Enthalpies of formation and stability of ferrihydrite (~Fe(OH)3), schwertmannite (~FeO(OH)3/4(SO4)1/8), and e-Fe2O3. Geochimica et Cosmochimica Acta 68, 1049-1059 -827100 (Ref.: 04maj/nav) Majzlan, J., Navrotsky, A., Schwertmann, U. (2004) Thermodynamics of iron oxides: Part III. Enthalpies of formation and stability of ferrihydrite (~Fe(OH)3), schwertmannite (~FeO(OH)3/4(SO4)1/8), and e-Fe2O3. Geochimica et Cosmochimica Acta 68, 1049-1059 132.589 (Ref.: Internal calculation) 101.67 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp.
CP(T) = a + b·T + ·c·T-2 (T in Kelvin)
a
J·mol-1·K-1
 b * 103
J·mol-1·K-2
 c * 10-5
J·K·mol-1
 Maier Kelley Ref.
101.67 0.00 0.00 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp.
Reaction properties

Ferrihydrite(2L) + 3H+ ⇌ Fe+3 + 3H2O

298.15 K, 1 bar log10K: 3.40 ΔH°r:-79390 J·mol-1 (Ref.: 04maj/nav) Majzlan, J., Navrotsky, A., Schwertmann, U. (2004) Thermodynamics of iron oxides: Part III. Enthalpies of formation and stability of ferrihydrite (~Fe(OH)3), schwertmannite (~FeO(OH)3/4(SO4)1/8), and e-Fe2O3. Geochimica et Cosmochimica Acta 68, 1049-1059
T(°C) 0 25 60 100 150 200 250 300
log10K 4.69 3.40 1.96 0.68 -0.56 -1.55 -2.40 -3.21
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-483.050578 -0.073766 28359.549410 172.734645 -1252681.664827