Analcime

Formula : Na0.99Al0.99Si2.01O6:H2O

Space group: 
Triclinic - Pedial H-M Symbol (1) Space Group: P1
Dana class: 
77.1.1.1 (77) Tectosilicate Zeolite group (77.1) true zeolites (77.1.1) Analcime and related species
High temperature: 
Low temperature mineral.
Geological context: 
Occurs frequently in basalts and other basic igneous rocks associated with other zeolites. In the groundmass or vesicles of silica-poor intermediate and mafic igneous rocks, typically basalts and phonolites, from late-stage hydrothermal solutions, or disseminated due to deuteric alteration. In lake beds, altered from pyroclastics or clays, or as a primary precipitate; occurs also as authigenic in sandstones and siltstones.

Dernière mise à jour le 11.06.2018

THERMODYNAMICS

Individual properties (298.15 K)
M
g·mol-1
cm3·mol-1
ΔGºf
J·mol-1
ΔHºf
J·mol-1
J·mol-1·k-1
CP
J·mol-1·K-1
219.935 96.680 -3089091 -3308000 231.100 212.38
Reaction properties

Analcime + 3.96H+ + 1.04H2O ⇌ 0.99Al+3 + 0.99Na+ + 2.01H4SiO4

298.15 K, 1 bar log10K: 6.64 ΔH°r: -102690 J·mol-1
T(°C) 0 25 60 100 150 200 250 300
log10K 8.29 6.64 4.77 3.09 1.44 0.10 -1.09 -2.22