Chemistry II AP Objectives

Links:

College Board Topic III:
Reactions

Topics:

4. Kinetics
   1. Concept of rate of reaction
   2. Use of experimental data and graphical analysis to determine reactant order, rate constants, and reaction rate laws
   3. Effect of temperature change on rates
   4. Energy of activation; the role of catalysts
   5. The relationship between the rate-determining step and a mechanism

Time Range:
See course calendar

Suggested Teaching Strategies:
III. D. 1-5: Introduce concept of reaction rate through the toothpick student activity. Have student graph disappearance of whole toothpicks and appearance of broken toothpicks. Use graphs to teach experiment rates, the relation of rate to concentration and how the rate expression changes if it is based on products rather than reactants. Use lab work to reinforce the dependence of rate on concentration and data analysis by differential rate laws. Introduce reaction orders and rate expressions. Through additional lab work, have students predict reaction rate expressions using the initial rate method. Teach the factors that effect reaction rate; temperature, particle size, concentration and catalyst, through demo and Addison Wesley lab. Use foil and ball analogy to start discussion on activation energy. Transition to Arrenhius equation. Conclude unit with analysis of reaction mechanism, elementary steps and rate determining step. A nice analogy to demo the reaction mechanism is the Lego or tinker toy race. Students form a team and build a model step by step, each student on the team performs one step. They analyze their process and identify the slow activity or rate determining step.

Aligned Resources:

• Core lab 13 - Rate Law Determination
• Brown and LeMay CD
• Wings Rate of Reaction video
• Wright State chem. demos

Revision Date:
May 2001