Kainite

Formula : KMgClSO4:3H2O

Family: 
Sulfates
Space group: 
Monoclinic - Prismatic HM symbol (2/m) Space Group: C 2/m
Dana class: 
31.7.1.13 2/m ; 31.7 Hydrated Sulfates Containing Hydroxyl or Halogen where (A+ B++)2 (XO4) Zq.x(H2O) ; 31.6.7

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
248.965 44.150 (Ref.: 95rob/hem) Robie R.A., and Hemingway B.S., 1995. Thermodynamic properties of minerals and related substances at 298.15 K and 1 Bar (105 Pascals) pressure and at higher temperatures. U.S. Geol. Survey Bull., 2131, 461 pp. -2325613 (Ref.: 84har/mol) Harvie C.E., Moller N., and Weare J.H.. 1984, The prediction of mineral solubilities in natural waters: The Na-K-Mg-Ca-H-Cl-SO4-OH-HCO3-CO3-CO2-H2O system to high ionic strengths at 25 C. Geochimica Cosmochimica Acta, 48, pp. 723-751. -2640100 (Ref.: 82wag/eva) Wagman D.D., Evans W.H., Parker V.B., Schumm R.H., Halow I., Bailey S.M., Churney K.L., and Nutall R.L., 1982. The NBS Tables of Chemical Thermodynamic Properties. J. Phys. Chem. Ref. Data, 11, Suppl. 2. 296.222 (Ref.: Internal calculation)
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

Kainite ⇌ Cl- + K+ + Mg+2 + SO4-2 + 3H2O

298.15 K, 1 bar log10K: -0.19 ΔH°r:-12950 J·mol-1 (Ref.: 82wag/eva) Wagman D.D., Evans W.H., Parker V.B., Schumm R.H., Halow I., Bailey S.M., Churney K.L., and Nutall R.L., 1982. The NBS Tables of Chemical Thermodynamic Properties. J. Phys. Chem. Ref. Data, 11, Suppl. 2.
T(°C) 0 25 60 100 150 200 250 300
log10K -0.03 -0.19 -0.46 -0.76 -1.16 -1.65 -2.38 -3.58
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-2534.783252 -0.384611 139262.461886 918.360598 -8022099.687082