Schwertmannite

Formula : Fe8O8(OH)6SO4:8H2O

Family: 
LDH
Space group: 
Tetragonal - Dipyramidal HM symbol (4/m) Space Group: P 4/m
Dana class: 
6.4.10.1VI - 6 Hydroxides and Oxides Containing Hydroxyl ; 6.4 Hydroxides and Oxides Containing Hydroxyl containing multiple cations ; 6.4.7

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
917.001 245.200 (Ref.: 90rob/cam) Roberts, Willard L., Campbell, Thomas J., and Rapp, George R.: Encyclopedia of Minerals. (Van Nostrand Reinhold Co., 2nd ed., 1990) -6040187 (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
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.
Reaction properties

Schwertmannite + 22H+ ⇌ 8Fe+3 + SO4-2 + 22H2O

298.15 K, 1 bar log10K: 8.98 ΔH°r: J·mol-1 (Ref.: )
T(°C) 0 25 60 100 150 200 250 300
log10K 8.98 8.98 8.98 8.98 8.98 8.98 8.98 8.98
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
8.982354 0.000000 0.000000 0.000000 0.000000