Foshagite

Formula : Ca4Si3O9(OH)2:0.5H2O

Space group: 
Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21/m
Dana class: 
65.2.2.1 (65) Inosilicate Single-Width Unbranched Chains, W=1(65.2) with chains P=3 (65.2.2) Dana Group
High temperature: 
High temperature mineral but..
Geological context: 
Metamorphosed limestone.

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
431.585 160.660 (Ref.: 63wyc) Wyckoff, R.W.G., 1963, Crystal Structures, Second edition, tome 4, Interscience Publishers, New York, p. 320-322. -5643923 (Ref.: 10abla/bou) Blanc, Ph.; Bourbon, X.; Lassin, A.; Gaucher, E.C. 2010 - Chemical model for cement-based materials: Temperature dependence of thermodynamic functions for nanocrystalline and crystalline C-S-H phases. Cement and Concrete Research, 40, p. 851-867 -6032430 (Ref.: 56new) Newman, E., 1956., Heats. of Formation of Xonotlite, Hillebrandite, and Foshagite: Journal of Research of the National Bureau of. Standards, v. 57, p. 27-30. 295.375 (Ref.: Internal calculation) 309.38 (Ref.: 10abla/bou) Blanc, Ph.; Bourbon, X.; Lassin, A.; Gaucher, E.C. 2010 - Chemical model for cement-based materials: Temperature dependence of thermodynamic functions for nanocrystalline and crystalline C-S-H phases. Cement and Concrete Research, 40, p. 851-867
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.
309.38 0.00 0.00 (Ref.: 10abla/bou) Blanc, Ph.; Bourbon, X.; Lassin, A.; Gaucher, E.C. 2010 - Chemical model for cement-based materials: Temperature dependence of thermodynamic functions for nanocrystalline and crystalline C-S-H phases. Cement and Concrete Research, 40, p. 851-867
Reaction properties

Foshagite + 8H+ + 0.5H2O ⇌ 4Ca+2 + 3H4SiO4

298.15 K, 1 bar log10K: 65.96 ΔH°r:-373238 J·mol-1 (Ref.: 56new) Newman, E., 1956., Heats. of Formation of Xonotlite, Hillebrandite, and Foshagite: Journal of Research of the National Bureau of. Standards, v. 57, p. 27-30.
T(°C) 0 25 60 100 150 200 250 300
log10K 71.85 65.96 59.05 52.74 46.58 41.72 37.68 34.10
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-2277.290939 -0.309197 152481.083255 814.831431 -8198974.535950