Vivianite

Formula : Fe3(PO4)2:8H2O

Family: 
Phosphates
Space group: 
Monoclinic - Prismatic HM symbol (2/m) Space Group: C 2/m
Dana class: 
40.3.6.1VII - 40 Hydrated Phosphates, etc ; 40.3 Hydrated Phosphates, etc where (A++)3 (XO4)2 . x(H2O) ; 40.3.6

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
501.606 185.096 (Ref.: 63wyc) Wyckoff, R.W.G., 1963, Crystal Structures, Second edition, tome 4, Interscience Publishers, New York, p. 320-322. -4461740 (Ref.: 94alb/tom) Al-Borno, A., Tomson, M.B. (1994) The temperature dependence of the solubility product constant of vivianite. Geochim. Cosmochim. Acta 58, 5373-5378
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

Vivianite + 4H+ ⇌ 3Fe+2 + 2H2PO4- + 8H2O

298.15 K, 1 bar log10K: -3.27 ΔH°r: J·mol-1 (Ref.: )
T(°C) 0 25 60 100 150 200 250 300
log10K -3.27 -3.27 -3.27 -3.27 -3.27 -3.27 -3.27 -3.27
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-3.271871 0.000000 0.000000 0.000000 0.000000