CHAPTER 12 EQUILIBRIUM CONDITIONS IN MULTICOMPONENT SYSTEMS
12.9 REACTIONEQUILIBRIA 409
If we treat H 2 O as a solvent and Ca^2 Cand HCO 3 as the solute species, then we write the
thermodynamic equilibrium constant as follows:
KD
aCa^2
aCaCO 3 aCO 2 aH 2 O
D r
(^) C (^) ^2 mCm^2 =.m/^3
fCO 2 =p
(^) H 2 OxH 2 O
(12.9.2)
The subscriptsCand refer to the Ca^2 Cand HCO 3 ions, and all quantities are for the
system at reaction equilibrium. ris the proper quotient of pressure factors, given for this
reaction by^15