Scorodite

Formula : FeAsO4:2H2O

Family: 
Arsenate
Space group: 
Orthorhombic - DipyramidalH-M Symbol (2/m 2/m 2/m) Space Group: Pcab

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
230.797 72.100 (Ref.: 00bla/bid) Bladh K.W., Bideaux R.A., Anthony-Morton E., Nichols B.G. (2000) The Handbook of Mineralogy Volume IV, Mineralogical Society of America. -1285791 (Ref.: 06lan/mah) Langmuir D, Mahoney J, Rowson J (2006) Solubility products of amorphous ferric arsenate and crystalline scorodite (Fe- AsO4_2H2O) and their application to arsenic behavior in buried mine tailings. Geochim Cosmochim Acta 70:2942-2956 -1508900 (Ref.: 11maj/dra) Majzlan J, Drahota P, Filippi M, Novak M, Loun J and Grevel K-D 2011. Thermodynamics of Crystalline iron(III) Arsenates Scorodite, Kankite, and Bukovskyite. Goldschmidt 2011 Conference Abstract 1391 191.514 (Ref.: Internal calculation) 180.54 (Ref.: 90pap/ber) V.G. Papangelakis, D. Berk and G.P. Demopoulos, Mathematical modeling of an exothermic leaching reaction system: pressure oxidation of wide size arsenopyrite particulates. Metall. Trans. B, 21B (1990), pp. 827-837.
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.
180.54 0.00 0.00 (Ref.: 90pap/ber) V.G. Papangelakis, D. Berk and G.P. Demopoulos, Mathematical modeling of an exothermic leaching reaction system: pressure oxidation of wide size arsenopyrite particulates. Metall. Trans. B, 21B (1990), pp. 827-837.
Reaction properties

Scorodite + 2H+ ⇌ H2AsO4- + Fe+3 + 2H2O

298.15 K, 1 bar log10K: -7.37 ΔH°r:-21409 J·mol-1 (Ref.: 11maj/dra) Majzlan J, Drahota P, Filippi M, Novak M, Loun J and Grevel K-D 2011. Thermodynamics of Crystalline iron(III) Arsenates Scorodite, Kankite, and Bukovskyite. Goldschmidt 2011 Conference Abstract 1391
T(°C) 0 25 60 100 150 200 250 300
log10K -7.05 -7.37 -7.79 -8.23 -8.77 -9.34 -10.00 -10.85
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-1036.533224 -0.165393 55820.815118 374.354808 -3116907.359670