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Mineral speciesFormula
 BoehmiteAlO(OH) 
Mineralogy
Family: Diaspore - Goethite - Faitknechtite series 
Space group: Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Amam 
Dana class: 6.1.2.1 (6)Hydroxides and Oxides Containing Hydroxyl (6.1)where X+++O OH (6.1.2)Dana Group 
Geological context
High temperature: Stable at room temperature 
Geological context: Major constituent of most bauxite ores that are secondary deposits from supergene alteration. 
Thermodynamics
Individual properties
Molar weight: 59.988 g/mol  ΔGºf-918,406 J/mol ref.  Sº: 37.20 J/mol/K ref. 
  ΔHºf-996,400 J/mol ref.  Cp: 54.24 J/mol/K ref. 
Reaction properties
Chemical reaction:  Boehmite + 3H+ = Al+3 + 2H2O 
log10(Keq) = A + B.T + C.T-1 + D.log10(T) + E.T−2 (with T expressed in Kelvin)
A B C D E
 -4.78462834e+2   -7.89260758e-2   2.97387698e+4   1.71482842e+2   -1.28427850e+6 
Van t'Hoff
@ 25°C, 1 bar: log 10(Keq)7.63
ΔH°r-113,660 J/mol ref.
T (ºC) : 0 25 60 100 150 200 250 300
log 10(Keq):  9.44   7.63   5.53   3.59   1.64   0.03   -1.40   -2.73 
Maier Kelley
Cp(T) = a + b*10-3T + C*105T-2 (with T expressed in Kelvin)  ref.
a:57.55 J/mol/K 
b:44.86 J/mol/K2 
c:-14.84 J.K/mol 

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