Pyroxene(CaAl)

Formula : CaAl(AlSi)O6

Family: 
Pyroxenes
Space group: 
See pyroxene
Dana class: 
See pyroxene
High temperature: 
High temperature mineral.
Geological context: 
ultramafic and mafic magmatic rocks, high grade metamorphic rocks such as calcsilicate gneisses, marbles, contact 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
218.123 63.500 (Ref.: 78hel/del,92ajoh) -3104808 (Ref.: 78hel/del,92ajoh) -3279529 (Ref.: Internal calculation) 146.440 (Ref.: 78hel/del,92ajoh) 164.36 (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.
226.48 26.86 -62.34 (Ref.: 78hel/del,92ajoh)
Reaction properties

Pyroxene(CaAl) + 8H+ ⇌ 2Al+3 + Ca+2 + H4SiO4 + 2H2O

298.15 K, 1 bar log10K: 36.23 ΔH°r:-370792 J·mol-1 (Ref.: Internal calculation)
T(°C) 0 25 60 100 150 200 250 300
log10K 42.12 36.23 29.36 22.99 16.58 11.31 6.75 2.58
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-1590.824300 -0.246039 104532.511796 568.193102 -4990965.928619