Chlorapatite(Pp)

Formula : Ca5(PO4)3Cl

Family: 
Phosphates
Space group: 
Monoclinic - Domatic HM symbol (m) Space Group: P 63/m 6/
Dana class: 
41.8.1.0VII - 41 Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen ; 41.8 Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen where(?)5 (XO4)3 Zq ; 41.8.1
High temperature: 
It is stable in a wide range of temperature. Its stability at room temperature is possible.
Geological context: 
Apatite is the most abundant naturally occuring phosphate on Earth. Occurs in metamorphic rocks, sedimentary environments or precipitate from hydrothermal solutions

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
520.756 163.880 (Ref.: 74nau/ryz) Naumov G.B., Ryzhenko B.N., and Khodakovsky I.L., 1974. Handbook of Thermodynamic Data. U.S. Geol. Surv.WRD 74 001, 328 pp. -6223750 (Ref.: 84vie/tar,after 72bduf) 398.97 (Ref.: 68val/kog) Valyashko V.M., Kogarko L.N., Khodakovsky I.L., 1968, Stability of fluorapatite, chlorapatite, and hydroxylapatite in aqueous solutions at different temperature. Geoch. Inter., 5, 21-30
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.
398.97 0.00 0.00 (Ref.: 68val/kog) Valyashko V.M., Kogarko L.N., Khodakovsky I.L., 1968, Stability of fluorapatite, chlorapatite, and hydroxylapatite in aqueous solutions at different temperature. Geoch. Inter., 5, 21-30
Reaction properties

Chlorapatite(Pp) + 6H+ ⇌ 5Ca+2 + Cl- + 3H2PO4-

298.15 K, 1 bar log10K: 14.53 ΔH°r: J·mol-1 (Ref.: )
T(°C) 0 25 60 100 150 200 250 300
log10K 14.53 14.53 14.53 14.53 14.53 14.53 14.53 14.53
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
14.533234 0.000000 0.000000 0.000000 0.000000