Scholzite

Formula : CaZn2(PO4)2:2H2O

Family: 
Phosphates
Space group: 
Orthorhombic - Dipyramidal HM symbol (2/m 2/m 2/m) Space Group: Pbmm
Dana class: 
40.2.6.1VII - 40 Hydrated Phosphates, etc ; 40.2 Hydrated Phosphates, etc where A++ (B++)2 (XO4) . x(H2O) ; 40.2.4

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
396.831 125.965 (Ref.: 63wyc) Wyckoff, R.W.G., 1963, Crystal Structures, Second edition, tome 4, Interscience Publishers, New York, p. 320-322. -3553471 (Ref.: 84nri) Nriagu J.O., 1984, Formation and stability of base metal phosphates in soils and sediments, Chap. 10. In: Phosphate Minerals, J.O. Nriagu and P.B. Moore (Eds), Springer-Verlag, ISBN 3-540-12757-7, 318-329
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

Scholzite + 4H+ ⇌ Ca+2 + 2H2PO4- + 2Zn+2 + 2H2O

298.15 K, 1 bar log10K: 7.43 ΔH°r: J·mol-1 (Ref.: )
T(°C) 0 25 60 100 150 200 250 300
log10K 7.43 7.43 7.43 7.43 7.43 7.43 7.43 7.43
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
7.425419 0.000000 0.000000 0.000000 0.000000