Lansfordite

Formula : MgCO3:5H2O

Family: 
Carbonates
Space group: 
Monoclinic - Prismatic HM symbol (2/m) Space Group: P 21/a
Dana class: 
15.1.6.1V - 15 Hydrated Carbonates ; 15.1 Hydrated Carbonates where A+ (XO3) . x(H2O) ; 14.4.6

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
174.390 101.988 (Ref.: 63wyc) Wyckoff, R.W.G., 1963, Crystal Structures, Second edition, tome 4, Interscience Publishers, New York, p. 320-322. -2197737 (Ref.: Internal calculation) -2574270 (Ref.: 99kon/kon) Konigsberger E., Konisberger L.C., and Gamsjager H., 1999. Low temperature thermodynamic model for the system Na2CO3 MgCO3 CaCO3 H2O. Geochimica et Cosmochimica Acta, 63, p. 3105-3119. 249.520 (Ref.: 99kon/kon) Konigsberger E., Konisberger L.C., and Gamsjager H., 1999. Low temperature thermodynamic model for the system Na2CO3 MgCO3 CaCO3 H2O. Geochimica et Cosmochimica Acta, 63, p. 3105-3119.
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

Lansfordite + H+ ⇌ HCO3- + Mg+2 + 5H2O

298.15 K, 1 bar log10K: 5.29 ΔH°r:-11810 J·mol-1 (Ref.: 99kon/kon) Konigsberger E., Konisberger L.C., and Gamsjager H., 1999. Low temperature thermodynamic model for the system Na2CO3 MgCO3 CaCO3 H2O. Geochimica et Cosmochimica Acta, 63, p. 3105-3119.
T(°C) 0 25 60 100 150 200 250 300
log10K 5.55 5.29 5.18 5.30 5.65 6.10 6.53 6.83
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-1033.978228 -0.139570 55526.821262 374.316927 -2806936.619389