AP Chemistry Kinetic Review

Collision Theory

1. In order for a reaction to occur, what three requirements are there according to the collision theory?

2. Draw a graph of energy vs. reaction time for an endothermic and an exothermic reaction. Label the activation energy and the ΔE for each.

3. What are factors that can affect a chemical reaction’s rate?

4. Explain why increasing the temperature generally increases the rate of a reaction?

5. Draw a graph of fraction of molecules vs. energy and show the distribution of molecular energies at various temperatures. Also be sure to label the activation energy on the graph.

6. Explain why increasing the surface area of a sample generally increases the rate of a reaction.

7. Explain why increasing the concentration of a sample generally increases the rate of a reaction.

8. What is a catalyst?

9. On the graphs you drew from problems #2 and #5 above, show how a catalyst would affect each graph.

10. For the following reaction, which species is acting as a catalyst? Which is an intermediate? Why?

Overall: O₃ + O —> 2 O₂

Step 1: Cl + O₃ —> ClO + O₂

Step 2: ClO + O —> Cl + O₂

Relative Rate and Rate Equations

11. For the following reaction, draw a graph showing concentration vs. time for each species. Assume you start with equal amounts of reactants, no products, and the reaction reaches equilibrium before any species runs out.

 CH₃Cl + 3Cl₂ --> CCl₄ + 3 HCl

12. Given the below initial rate data, determine the rate law and rate constant (be sure to include accurate units) for the following reaction:

Mechanisms

13. For the following reaction: AB + C --> A + BC, the following mechanism is proposed: Write the rate law based upon this information.

Step 1: AB + AB --> AB₂ + A     slow

Step 2: AB₂ + C --> AB + BC     fast

Integrate Rate Laws

The following is data for the reaction:

N₂O₅ --> NO₃ + NO₂

 a. What is the order for the reactant N₂O₅?

b. Write the rate law.

c. What is the value for k?

d. What would the concentration be at 500 seconds?

e. What is the half-life of the reaction?