1. The document discusses collision theory and how various factors affect the rate of a chemical reaction. It defines rate of reaction and lists collision frequency, number of particles with energy greater than or equal to the activation energy, and proper collision geometry as factors that reaction rate depends on. 2. It explains Maxwell-Boltzmann distribution and how increasing temperature, concentration, pressure, decreasing particle size, or adding a catalyst can increase the rate of reaction by altering the distribution. 3. It defines a catalyst as a substance that speeds up a reaction by providing an alternative reaction pathway with a lower activation energy, but is unchanged at the end and recovered in the same amount.

1. Define
1. Rate of reaction
2. http://www.youtube.com/watch?v=
085e-ALKmUM&feature=related

2. Aims
• Collision theory.
• State Maxwell Boltzmandistrubution and how
factors affect it.
• Review exam style questions.

3. Collision Theory
• reaction rate depends on:
– collision frequency
– number of particles with E ≥ Ea
– appropriate collision geometry or orientation.

4. Collision Theory
• http://www.animatedscience.com.au/learning
modules/46.swf
• YIKES ! The last slide doesn’t work – you need
to fix this ! Please draw how
Temperature, Concentration, Pressure, Particle
Size and Catalyst alter rate of reaction.

5. Maxwell Boltzman Distribution

6. At a Higher Temperature..

7. Maxwell Boltzman with Catalyst

8. The Effect of a Catalyst
• A catalyst provides an alternative route for the
reaction with a lower activation energy. THE
ORIGINAL ACTIVATION ENERGY IS
UNCHANGED !

9. What is a Catalyst ?
• A catalyst is a tbsscanue which speeds up a
reaction, but isllyaccmiheunchanged at the
end of the rnciotea. When the reaction has
finished, you would havetelcaxythe same
mass of catalyst as you had at the beginning.

10. Graphs You Must be Able to Sketch
• 1. Vol of gas vs time
• 2. Mass vs time
• 3. Compare particle size on same graph
• 4. Compare T&P on same graph
• 5. Concentration of reactants and products vs
time
• 6. Rate vs time

11. Exam Style Questions
• Packs 

12. (Back up) Practical Techniques
• Describe a method to study the kinetics of the
traffic light reaction we did yesterday.
• (Use criteria sheet)