22. The equilibrium constant for the formation of calcium carbonate from the ions in solution is 2.2 × 10⁸ according to the reaction:

Ca²⁺(aq) + CO₃^2–(aq) <=> CaCO₃(s) K = 2.2 × 10⁸.

What is the value of the equilibrium constant for the reverse of this reaction?

CaCO₃(s) <=> Ca²⁺(aq) + CO₃ ^2–(aq) K = ?????

2. Which of the following is true regarding the concentration of products, for a chemical reaction that is already at equilibrium, assuming no disruptions to the equilibrium?

The following rate constants were obtained in an experiment in which the decomposition of gaseous N₂O₅ was studied as a function of temperature. The products were NO₂ and NO₃.

   T (^oC)           k (s^-1)       

   41            0,31

   88            7,3

Determine Ea for this reaction in kJ/mol.  

Many reactions occur in the formation of photochemical smog, including the reaction of ozone with various volatile organic chemicals, or VOCs. The table in the next column shows the Arrhenius expression for four such reactions.

Identify the highest rate constant at 25 ^oC among the Arrhenius equations above. 

35. A reaction X + 2Y → 3Z is started with 1.0 M Z and no X or Y. To calculate the equilibrium concentrations of all species using an ICE table, which of the following would you enter in the Z column for the C row?

51. Increasing the temperature of an exothermic reaction results in __________

1. Which of the following is true for a chemical reaction at equilibrium?

33. In the ICE table started for calculating equilibrium concentrations of the reaction shown, the three terms in the “change” row are __________

55. Given: 2A(g) <=> B(g) + C(g) ΔH° = +27 kJ, K = 3.2 x 10^-4.

Which of the following would be true if the temperature were increased from 25°C to 100°C?

1. The value of K would be smaller.

2. The concentration of A(g) would be increased.

3. The concentration of B(g) would increase.

42. The energy profiles for four different reactions are shown. Which reaction requires the most energetic collisions to reach the transition state?