Malachite

Formula : Cu2(OH)2(CO3)

Family: 
Carbonates
Space group: 
Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21/a
Dana class: 
16a.3.2.1 (16a) Carbonates - Hydroxyl or Halogen (16a.3) where (A B)2 (XO3) Zq (16a.3.2)Malachite Group
High temperature: 
Malachite is a supergene mineral.
Geological context: 
Secondary mineral in the oxidized zones of copper ore 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
221.116 54.860 (Ref.: 78hel/del) Helgeson, H.C., Delany, J.M, Nesbitt, H.W., and Bird, D.K., 1978. Summary and Critique of the Thermodynamic Properties of Rock Forming Minerals: Amer. J. Sci., 278A, 229 pp. -901535 (Ref.: 07pow/bro) Powell, K.J., Brown, P.L., Byrne, R.H., Gadja, T., Hefter, G., Sjoberg, S., Wanner, H., 2007. Chemical speciation of environmentally significant metals with inorganic ligands Part 2 : The Cu[2+]-OH[-], Cl[-], CO[3][2-], SO[4][2-], and PO[4][3-] systems : (IUPAC Technical Report). Pure and applied chemistry, USA. -1065309 (Ref.: Internal calculation) 166.300 (Ref.: 00pui) Puigdomenech, I., 2000. Thermodynamic data for copper: implications for the corrosion of copper under repository conditions, SKB report. SKB/Swedish Nuclear Fuel and Waste Management, p. 96. 140.54 (Ref.: 00pui) Puigdomenech, I., 2000. Thermodynamic data for copper: implications for the corrosion of copper under repository conditions, SKB report. SKB/Swedish Nuclear Fuel and Waste Management, p. 96.
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.
49.57 328.36 -6.16 (Ref.: 00pui) Puigdomenech, I., 2000. Thermodynamic data for copper: implications for the corrosion of copper under repository conditions, SKB report. SKB/Swedish Nuclear Fuel and Waste Management, p. 96.
Reaction properties

Malachite + 3H+ ⇌ HCO3- + 2Cu+2 + 2H2O

298.15 K, 1 bar log10K: 5.17 ΔH°r:-65926 J·mol-1 (Ref.: Internal calculation)
T(°C) 0 25 60 100 150 200 250 300
log10K 6.22 5.17 3.95 2.82 1.65 0.59 -0.47 -1.69
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-1285.496163 -0.202950 71071.352844 466.799190 -3756722.212568