Hvermiculite(K)

Formula : K0.86Mg3.00Si3.14Al0.86O10(OH)2:3.319H2O

Space group: 
Monoclinic - Prismatic HM symbol (2/m) Space Group: C 2/m
Dana class: 
71.3.1b.2VIII- 71 Phyllosilicate Minerals ; 71.3 Phyllosilicates Phyllosilicate Sheets of Six-Membered Rings with 2:1 clays ; 71.3.1b Smectite group (Trioctahedral Smectites)
High temperature: 
Low temperature mineral. At higher temperatures(> 500C), detachment of (OH) ions takes place.
Geological context: 
see vermiculite

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
471.734 207.534 (Ref.: 15bla/vie, 11vie/bla) -6585026 (Ref.: Internal calculation) -7124182 (Ref.: 15bla/vie, 11vie/bla) 564.465 (Ref.: 15bla/vie, 11vie/bla) 599.55 (Ref.: 15bla/vie, 11vie/bla)
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.
599.55 0.00 0.00 (Ref.: 15bla/vie, 11vie/bla)
Reaction properties

Hvermiculite(K) + 9.44H+ ⇌ 0.86Al+3 + 0.86K+ + 3Mg+2 + 3.14H4SiO4

298.15 K, 1 bar log10K: 36.58 ΔH°r:-326110 J·mol-1 (Ref.: 15bla/vie, 11vie/bla)
T(°C) 0 25 60 100 150 200 250 300
log10K 41.69 36.58 30.52 24.98 19.56 15.26 11.62 8.30
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-2652.026536 -0.360776 170245.833393 942.192144 -9443301.409116