Cotunnite

Formula : PbCl2

Family: 
Chlorides
Space group: 
Orthorhombic - Dipyramidal HM symbol (2/m 2/m 2/m) Space Group: Pnam
Dana class: 
9.2.7.1IV- 9 Halide Minerals ; 9.2 Anhydrous and Hydrated Halides where A(?)2 ; 9.2.7
High temperature: 
low temperature (surface)
Geological context: 
oxidized lead deposits

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
278.105 47.540 (Ref.: 84pan) Pankratz L. B., 1984, Thermodynamic Properties of Halides (U. S. Bureau of Mines Bulletin 674, 1984, 826 p). -314111 (Ref.: Internal calculation) -359400 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp. 135.980 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp. 77.08 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp.
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.
68.80 28.56 -0.21 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp.
Reaction properties

Cotunnite ⇌ 2Cl- + Pb+2

298.15 K, 1 bar log10K: -4.81 ΔH°r:26160 J·mol-1 (Ref.: 98cha) Chase, M.W.J., 1998. NIST-JANAF Thermochemical Tables, Journal of Physical Chemistry Reference Data, Vol. 9, 4th Edition. National Institute of Standards and Technology, Washington DC, 1951 pp.
T(°C) 0 25 60 100 150 200 250 300
log10K -5.31 -4.81 -4.43 -4.29 -4.43 -4.84 -5.54 -6.63
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-1528.573699 -0.248475 82798.391282 556.648997 -5089047.072273