SOLVED

31) In a reaction at equilibrium involving only gases, a change in pressure of the reaction mixture shifts the position of equilibrium only when: A) heat is absorbed by the reaction proceeding to the right B) the gases are impure C) the collision rate increases D) the reaction is exothermic as written E) the moles of gas are not equal on the two sides of the equation. 32) For the reaction: 3 Fe(s) + 4 H2O(g) ? Fe3O4(s) + 4 H2(g) what is the effect of removing H2? A) The reaction shifts to the right. B) There is no change. C) The reaction shifts to the left. D) The Kp is decreased. E) The Kp is doubled. 33) For the reaction: 3 Fe(s) + 4 H2O(g) ? Fe3O4(s) + 4 H2(g) what is the effect on equilibrium of increasing temperature of an exothermic reaction? A) The reaction shifts to the right. B) There is no change. C) The reaction shifts to the left. D) The Kp is decreased. E) The Kp is doubled. 34) According to Le Chatelier’s Principle: A) an increase in pressure always causes a change in the position of equilibrium for any reaction B) the greatest yield of ammonia in the exothermic reaction N2 + 3H2 ? 2NH3 is attained at a high temperature C) the equilibrium constant is increased for the reaction A + B ? C if the concentration of A is increased D) an increase of temperature causes a decrease in the value of the equilibrium constant for an exothermic reaction E) when an equilibrium system is stressed, the system reacts to offset the stress 35) Which of the following keep the equilibrium position unchanged? A) temperature decrease B) concentration change C) temperature D) pressure change E) homogeneous catalyst 36) Consider the reaction: CH4(g) + 4 Cl2(g) ? CCl4(l) + 4 HCl(g) ΔH° -398 kJ/mol The equilibrium is displaced to the right if: A) the temperature is raised B) the pressure is lowered C) some carbon tetrachloride is removed D) some hydrogen chloride is added E) some chlorine gas is removed 37) Choose the correct statement about a container in which the chemical equilibrium is established: 2 SO2(g) + O2(g) ? 2 SO3(g) + heat A) A decrease in amount of O2 will decrease the amount of SO2 present. B) A decrease in the volume will decrease the amount of SO2 present. C) A decrease in temperature will increase the amount of SO2 present. D) A decrease in the amount of SO3 present will increase the amount of SO2 present. E) An increase in amount of O2 will increase the amount of SO2 present. 38) Choose the correct statement about the equilibrium: N2(g) + 3 H2(g) ? 2 NH3(g), Kp = 1 × 10-4 atm-2 A) The rate constant for the forward reaction is greater than that of the reverse reaction. B) Since the reaction has a high activation energy, a catalyst is not needed. C) The equilibrium constant is given by Kp = [N2][H2]3/[NH3]2. D) Conducting the reaction under high pressures will increase the yield of ammonia. E) The Kp is independent of temperature. 39) Consider the exothermic reaction: 4 HCl(aq) + MnO2(s) ? Cl2(g) + 2 H2O(l) + MnCl2(aq) The equilibrium is displaced to the left if: A) catalyst is added B) pressure is lowered C) temperature is lowered D) H2O(l) is added E) MnO2 (s) is added 40) Consider the reaction: 2SO2(g) + O2(g) ? 2SO3(g) ΔH° = -196.6 kJ/mol The equilibrium is displaced to the left if: A) some sulfur trioxide is removed B) the temperature is raised C) some sulfur dioxide is added D) the pressure is raised E) the temperature is lowered