Cassiterite

Formula : SnO2

Family: 
Space group: 
Tetragonal - Ditetragonal Dipyramidal H-M Symbol (4/m 2/m 2/m) Space Group: P 4/mnm
Dana class: 
4.4.1.5 (4)Simple Oxides 4.4)with a cation charge of 4+ (A++++ O2) (4.4.1)Rutile group (Tetragonal: P4/mnm)
High temperature: 
Possible stability around 100C in laboratory experiments, in a natural environnement : hydrothermal and present in magmatic rocks during late pneumatolitic stage; but some data allows to suppose a cassiterite stable during the weathering stage of tin sul
Geological context: 
Occurs in granite pegmatites and alluvial placer deposits.

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
150.709 28.900 -515826 -577630 49.040 53.22
Reaction properties

Cassiterite + 2H+ ⇌ Sn+2 + 0.5O2 + H2O

298.15 K, 1 bar log10K: -45.46 ΔH°r: 276957 J·mol-1
T(°C) 0 25 60 100 150 200 250 300
log10K -49.88 -45.46 -40.34 -35.61 -30.93 -27.22 -24.22 -21.78