CH 102 Spring 2026 – Discussion Worksheet 6 Name: ________________________________________
1. Discuss the following important concepts with your group. Check in with your TF or LA about your answers.
a. [McQuarrie 19–55] What does the magnitude of the equilibrium constant (𝐾! ) tell you about a reaction?
b. [McQuarrie 19–57] Prior to learning about equilibrium states, we solved stoichiometric problems using the
concept of “limiting reactants” with 100% yield. Under what conditions do we expect 100% yield?
c. [McQuarrie 19–58] What is the difference between the equilibrium constant, Kc, and the reaction quotient, Qc?
d. What happens if the reaction quotient, Qc, is large? Explain.
2. [McQuarrie 19–3] Write the equilibrium-constant expression (Kc) for the reactions. What are the units of Kc in each?
a. ZnO(𝑠) + CO(𝑔) ⇌ Zn(𝑙) + CO2(𝑔) b. 2 C5H6(𝑔) ⇌ C10H12(𝑔) c. 2 N2O5(𝑎𝑞) ⇌ 4 NO2(𝑎𝑞) + O2(𝑔)
3. [McQuarrie 19–17] Given that [Ni(CO)4] = 0.85 M at equilibrium for the equation Ni(𝑠) + 4 CO(𝑔) ⇌ Ni(CO)4(𝑔) with
Kc = 5.0 × 104 M–3, calculate the concentration of CO(𝑔) at equilibrium.
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1. Discuss the following important concepts with your group. Check in with your TF or LA about your answers.
a. [McQuarrie 19–55] What does the magnitude of the equilibrium constant (𝐾! ) tell you about a reaction?
b. [McQuarrie 19–57] Prior to learning about equilibrium states, we solved stoichiometric problems using the
concept of “limiting reactants” with 100% yield. Under what conditions do we expect 100% yield?
c. [McQuarrie 19–58] What is the difference between the equilibrium constant, Kc, and the reaction quotient, Qc?
d. What happens if the reaction quotient, Qc, is large? Explain.
2. [McQuarrie 19–3] Write the equilibrium-constant expression (Kc) for the reactions. What are the units of Kc in each?
a. ZnO(𝑠) + CO(𝑔) ⇌ Zn(𝑙) + CO2(𝑔) b. 2 C5H6(𝑔) ⇌ C10H12(𝑔) c. 2 N2O5(𝑎𝑞) ⇌ 4 NO2(𝑎𝑞) + O2(𝑔)
3. [McQuarrie 19–17] Given that [Ni(CO)4] = 0.85 M at equilibrium for the equation Ni(𝑠) + 4 CO(𝑔) ⇌ Ni(CO)4(𝑔) with
Kc = 5.0 × 104 M–3, calculate the concentration of CO(𝑔) at equilibrium.
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