Anhydrite

Formula : CaSO4

Space group: 
Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Amma
Dana class: 
28.3.2.1 (28) Anhydrous Acid and Sulfates (28.3)(A++) XO4 (28.3.2) Dana Group
High temperature: 
Low and high temperature stability.
Geological context: 
Hydrothermal and sedimentary to igneous mineral.

Dernière mise à jour le 19.12.2017

THERMODYNAMICS

Individual properties (298.15 K)
M
g·mol-1
cm3·mol-1
ΔGºf
kJ·mol-1
ΔHºf
kJ·mol-1
J·mol-1·k-1
CP
J·mol-1·K-1
136.142 46.010 -1.322.132 -1.434.400 107.400 101.23
Reaction properties

Anhydrite ⇌ Ca+2 + SO4-2

298.15 K, 1 bar log10K: -4.44 ΔH°r: -17940 J·mol-1
T(°C) 0 25 60 100 150 200 250 300
log10K -4.24 -4.44 -4.88 -5.50 -6.39 -7.42 -8.64 -10.19