Pyromorphite

Formula : Pb5(PO4)3OH

Family: 
Phosphates
Space group: 
Monoclinic - Domatic HM symbol (m) Space Group: P 63/m 6/
Dana class: 
41.8.4.1VII - 41 Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen ; 41.8 Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen where(?)5 (XO4)3 Zq ; 41.8.4

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
1337.920 188.400 (Ref.: 90rob/cam) Roberts, Willard L., Campbell, Thomas J., and Rapp, George R.: Encyclopedia of Minerals. (Van Nostrand Reinhold Co., 2nd ed., 1990) -3873214 (Ref.: 74nri) Nriagu J.O., 1974. Lead orthophosphates-IV Formation and stability in the environment. Geochimica et Cosmochimica Acta, 38, p. 887 898.
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

Pyromorphite + 7H+ ⇌ 3H2PO4- + 5Pb+2 + H2O

298.15 K, 1 bar log10K: -18.12 ΔH°r: J·mol-1 (Ref.: )
T(°C) 0 25 60 100 150 200 250 300
log10K -18.12 -18.12 -18.12 -18.12 -18.12 -18.12 -18.12 -18.12
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-18.118984 0.000000 0.000000 0.000000 0.000000