Q1. What is the equilibrium constant (Kc) for the reaction: A + B ⇌ C + D? (2022)
Solution:
The equilibrium constant Kc is defined as the ratio of the concentrations of the products to the reactants, each raised to the power of their coefficients in the balanced equation.
⏱ Time: 0s
Q2. For the reaction N2(g) + 3H2(g) ⇌ 2NH3(g), what happens to the equilibrium if the volume of the container is decreased? (2020)
Solution:
Decreasing the volume increases the pressure, and according to Le Chatelier's principle, the equilibrium will shift to the side with fewer moles of gas, which is the right side in this case.
⏱ Time: 0s
Q3. For the reaction 2SO2(g) + O2(g) ⇌ 2SO3(g), what happens to the equilibrium position if SO3 is removed from the system? (2023)
Solution:
Removing SO3 will decrease its concentration, causing the system to shift to the right to produce more SO3 in order to re-establish equilibrium, according to Le Chatelier's principle.
⏱ Time: 0s
Q4. In a reversible reaction, if the concentration of products increases, what happens to the equilibrium position? (2021) 2021
Solution:
According to Le Chatelier's principle, if the concentration of products increases, the equilibrium will shift to the left to counteract the change.
⏱ Time: 0s
Q5. In the reaction CO(g) + 2H2(g) ⇌ CH3OH(g), what effect does increasing the temperature have if the reaction is exothermic? (2020)
Solution:
For an exothermic reaction, increasing the temperature shifts the equilibrium to the left, favoring the reactants, as the system tries to absorb the added heat.
⏱ Time: 0s
Q6. For the reaction A(g) + B(g) ⇌ C(g), if the concentration of C is increased, what will be the effect on the equilibrium? (2020)
Solution:
Increasing the concentration of a product (C) will shift the equilibrium to the left to counteract the change, according to Le Chatelier's principle.
⏱ Time: 0s
Q7. In a reversible reaction at equilibrium, which of the following statements is true?
Solution:
At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction, which means the concentrations of reactants and products remain constant over time.
⏱ Time: 0s
Q8. In a reversible reaction at equilibrium, if the temperature is increased, what will happen to the equilibrium position if the reaction is exothermic? (2023)
Solution:
For an exothermic reaction, increasing the temperature shifts the equilibrium position to the left, favoring the reactants, as the system tries to absorb the added heat.
⏱ Time: 0s
Q9. Which of the following changes will not affect the position of equilibrium in the reaction N2(g) + 3H2(g) ⇌ 2NH3(g)? (2021)
Solution:
A catalyst speeds up the rate of both the forward and reverse reactions equally, thus it does not affect the position of equilibrium. Other changes like temperature, pressure, and concentration of reactants/products do affect the equilibrium.
⏱ Time: 0s
Q10. Which of the following changes will shift the equilibrium to the right in the reaction: N2(g) + 3H2(g) ⇌ 2NH3(g)? (2021)
Solution:
Increasing the pressure will shift the equilibrium to the side with fewer moles of gas, which is the right side (2 moles of NH3) in this case.
