co hco caco h co p - mit opencourseware · 2020. 12. 31. · 1 3 5 7 co 3 a 2 hco 3 -caco 3 (s)...
TRANSCRIPT
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1 3 5 7
CO3
a
2
HCO3 -
CaCO3 (s)
(Ca2+)max
H2CO3
PCO2 Fixed
Log C-pH diagram for Ca2+ and carbonate at equilibrium with PCO2 = 10-3.5 atm
and CaCO3hatched area of the graph is supersaturated with respect to CaCO3(calcite); at equilibrium the free calcium concentration and the pH must yield a point on the
the condition [HCO3 -] = 2[Ca2+
from the intersection of the corresponding vertical line the graphs of the various species.
*
pH 9 13
-9
-7
-5
-3
Log
C
-1
+1 1o of freedom if aqueous fluid, CO2 (q) at fixed PCO2, and CaCO3(s)
T)
-11
P, T, and
(s). A system whose calcium concentration and pH yield a point in the
saturation line of the diagram. The solution is given by point a, which satisfies ]. The composition of the system is then obtained
11
are in eq at fixed P, T (so if no P, T, no [Ca]
Figure by MIT OCW.