Aragonite

Formula : CaCO3

Family: 
Carbonates
Space group: 
Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pmcn
Dana class: 
14.1.3.1 (14) Anhydrous Carbonates (14.1) with Simple Formula A+ CO3 (14.1.3) Aragonite Group (Orthorhombic: Pmcn)
High temperature: 
Very low temperature mineral <50C in hydrothermal systems
Geological context: 
Widespread mineral in hydrothemal systems and also as a biological secretion.

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
100.087 34.150 (Ref.: 78hel/del,82plu/bus) -1128154 (Ref.: Internal calculation) -1207780 (Ref.: 87gar/par) CODATA87 Garvin D., Parker V.B and White H.J., 1987. CODATA Series on Thermodynamic Properties, Hemisphere, Washington, DC. 87.990 (Ref.: 87gar/par) CODATA87 Garvin D., Parker V.B and White H.J., 1987. CODATA Series on Thermodynamic Properties, Hemisphere, Washington, DC. 82.32 (Ref.: 87gar/par) CODATA87 Garvin D., Parker V.B and White H.J., 1987. CODATA Series on Thermodynamic Properties, Hemisphere, Washington, DC.
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.
82.32 0.00 0.00 (Ref.: 87gar/par) CODATA87 Garvin D., Parker V.B and White H.J., 1987. CODATA Series on Thermodynamic Properties, Hemisphere, Washington, DC.
Reaction properties

Aragonite + H+ ⇌ HCO3- + Ca+2

298.15 K, 1 bar log10K: 2.01 ΔH°r:-25150 J·mol-1 (Ref.: 87gar/par) CODATA87 Garvin D., Parker V.B and White H.J., 1987. CODATA Series on Thermodynamic Properties, Hemisphere, Washington, DC.
T(°C) 0 25 60 100 150 200 250 300
log10K 2.39 2.01 1.51 0.97 0.31 -0.36 -1.08 -1.96
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-859.027300 -0.139090 47686.137170 312.468022 -2721065.014429