Consider the following two reactions occurring simultaneously in the same vessel at…

CHEMISTRY · Single correct · AP · Chemistry · Equilibrium · Equilibrium

Problem

Consider the following two reactions occurring simultaneously in the same vessel at 1000\,K using the same instantaneous concentration data: (1)\;

\text{CO}(g) + \tfrac{1}{2}\,\text{O}_2(g) \rightleftharpoons \text{CO}_2(g)

Q_1 = 2.5

\; ;\;

K_1 = 1.0

(2)\;

\text{H}_2(g) + \tfrac{1}{2}\,\text{O}_2(g) \rightleftharpoons \text{H}_2\text{O}(g)

Q_2 = 0.40

\; ;\;

K_2 = 0.50

The reactions can be summed to give the overall reaction:

\text{CO}(g) + \text{H}_2(g) + \text{O}_2(g) \rightleftharpoons \text{CO}_2(g) + \text{H}_2\text{O}(g)

Which statement correctly describes the relationship between the overall reaction quotient

Q_{\text{overall}}

and the overall equilibrium constant

K_{\text{overall}}

, and predicts the direction the system will shift? (a)

Q_{\text{overall}} = 2.9

and

Q_{\text{overall}} > K_{\text{overall}}

; the mixture will shift toward reactants. (b)

Q_{\text{overall}} = 0.50

and

Q_{\text{overall}} = K_{\text{overall}}

; the mixture is at equilibrium. (c)

Q_{\text{overall}} = 1.0

and

Q_{\text{overall}} > K_{\text{overall}}

; the mixture will shift toward reactants. (d)

Q_{\text{overall}} = 0.20

and

Q_{\text{overall}} < K_{\text{overall}}

; the mixture will shift toward products.