Consider the heterogeneous equilibrium reaction occurring at 450K:
CaCO3(s)⇌CaO(s)+CO2(g)
A rigid 5.00L container at 450K initially contains 0.612g of CO2 gas together with excess solid CaCO3 and CaO. During an experiment, an additional 1.20×104Pa of argon gas is injected into the container at constant temperature. The equilibrium constant expressed in terms of partial pressure for the decomposition of CaCO3 at 450K is Kp=1.10×104Pa.
(a) Calculate the value of the reaction quotient Qp immediately after the argon is added but before any further reaction occurs. Clearly indicate which gaseous species are included in the expression.
(b) Predict whether additional CaCO3 will decompose, additional CO2 will be consumed, or no net reaction will occur as the system returns to equilibrium. Support your prediction quantitatively.
(c) Explain why the injection of argon changes the total pressure yet does not appear explicitly in the equilibrium expression you wrote in part (a).