41. In an exothermic reaction, what will happen if the temperature is decreased?

  • A) Equilibrium will shift towards the products
  • B) Equilibrium will shift towards the reactants
  • C) No change in equilibrium
  • D) The reaction will stop
  • Answer: A

42. Which of the following changes would shift the equilibrium of a reaction to favor the products?

  • A) Adding more products
  • B) Adding more reactants
  • C) Removing reactants
  • D) Increasing temperature for an exothermic reaction
  • Answer: B

43. For a reversible reaction at equilibrium, what happens when a product is removed?

  • A) The reaction will stop
  • B) Equilibrium will shift to produce more products
  • C) The rate of the forward reaction will decrease
  • D) The reverse reaction will dominate
  • Answer: B

44. Le Chatelier’s principle can be used to explain why increasing pressure in a reaction involving gases:

  • A) Shifts equilibrium towards the side with more gas molecules
  • B) Shifts equilibrium towards the side with fewer gas molecules
  • C) Has no effect on equilibrium
  • D) Increases the rate of the reverse reaction
  • Answer: B

45. In an exothermic reaction, decreasing the temperature will:

  • A) Shift equilibrium towards the reactants
  • B) Shift equilibrium towards the products
  • C) Have no effect on equilibrium
  • D) Stop the reaction entirely
  • Answer: B

46. According to Le Chatelier’s principle, adding heat to an endothermic reaction will:

  • A) Shift equilibrium to the right
  • B) Shift equilibrium to the left
  • C) Increase the concentration of products
  • D) Have no effect
  • Answer: A

47. In a chemical equilibrium, if pressure is decreased, the system will shift to:

  • A) The side with fewer moles of gas
  • B) The side with more moles of gas
  • C) The side with an equal number of moles
  • D) The reactants
  • Answer: B

48. What happens if a catalyst is added to a system at equilibrium?

  • A) Equilibrium shifts to the right
  • B) Equilibrium shifts to the left
  • C) Both the forward and reverse reactions are sped up
  • D) Only the forward reaction is sped up
  • Answer: C

49. Which of the following factors does not affect the position of equilibrium?

  • A) Pressure
  • B) Temperature
  • C) Concentration
  • D) Catalyst
  • Answer: D

50. If the pressure on the following equilibrium system is increased, 2NO₂ ⇌ N₂O₄, the position of equilibrium will:

  • A) Shift to the right
  • B) Shift to the left
  • C) Not change
  • D) Stop the reaction
  • Answer: A