Posted by Jill on .
Ca(HCO3)2(s) decomposes at elevated temperatures according to the stoichiometric equation Ca(HCO3)2(s)> CaCO3(s) + H2O(g) + CO2(g)
a.) If pure Ca(HCO3)2(s) is put into a sealed vessel, the air is pumped out, and the vessel and its contents are heated, the total pressure is 0.235 bar. Determine Kp under these conditions.
b.) If the vessel initially also contains 0.105 bar H2O(g), what is the partial pressure of CO2(g) at equilibrium?

Chemistry. 
DrBob222,
Ca(HCO3)2(s)> CaCO3(s) + H2O(g) + CO2(g)
Total pressure is 0.235 bar. Since the mole ratio is 1:1, the partial pressure H2O and partial pressure of CO2 must be the same; therefore, 2x = 0.235 and x = 0.235/2.
Then Kp = P(CO2)*P(H2O) = ??
b).
.....CO2 + H2O
...0.105 bar..0
.... + x....+x
final is 0.105+x and x
Substitute into Kp expression and solve for x.