Andradite

Formula : Ca3Fe2Si3O12

Family: 
Garnet
Space group: 
Isometric - Hexoctahedral H-M Symbol (4/m 3 2/m) Space Group: I a3d
Dana class: 
51.4.3b.1 (51) Nesosilicate Insular SiO4 Groups Only (51.4) with cations in [6] and >[6] coordination (51.4.3b) Garnet group (Ugrandite series)
High temperature: 
High temperature mineral.
Geological context: 
Igneous or metamorphic rocks, Fe skarns

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
508.177 131.850 (Ref.: 78hel/del,92ajoh) -5425891 (Ref.: 78hel/del,92ajoh) -5775718 (Ref.: Internal calculation) 293.424 (Ref.: 78hel/del,92ajoh) 349.14 (Ref.: 78hel/del,92ajoh)
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.
475.02 65.42 -129.24 (Ref.: 78hel/del,92ajoh)
Reaction properties

Andradite + 12H+ ⇌ 3Ca+2 + 2Fe+3 + 3H4SiO4

298.15 K, 1 bar log10K: 33.79 ΔH°r:-327864 J·mol-1 (Ref.: Internal calculation)
T(°C) 0 25 60 100 150 200 250 300
log10K 38.93 33.79 27.68 22.01 16.34 11.65 7.51 3.55
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-2907.783744 -0.423729 179814.931492 1040.602024 -9787021.291987