1. Collision Theory Factors affecting rate Investigate how temperature affects rate

2. Collision Theory 1.For a reaction to occur the particles must collide 2.The colliding particles must have a minimum energy called the Activation Energy

3. Factors affecting Rate of reaction 1.Concentration 2. Temperature 3.Particle size 4.Nature of reactants 5.Presence of a catalyst

4. Temperature, Collisions & Activation Energy Next slide

5. Effect of temperature on rate Increasing temperature increases the rate By increasing the number of collisions / sec More of the colliding particles have E Act

6. The formation of a pale yellow precipitate of sulphur can be used to monitor the progress of the reaction HClNa 2 S 2 O 3 H2OH2O + NaCl Investigate the effect of temperature on reaction rate ++ S + SO 2

7. To investigate the effect of temperature on reaction rate Next slide Add the HCl to the Na 2 S 2 O 3 in the flask Record the time taken for the X to disappear Record the temperature after mixing Inverse the time to get the rate

8. Next slide Repeat at different temperatures

9. Effect of temperature on rate RATERATE TEMPERATURE Conclusion ? Rate increases with increasing temperature 1 Time

10. Effect of temperature on rate RATERATE TEMPERATURE What is the main factor increasing rate between A and B Rate increases due to increased collisions /sec 1 Time A B

11. Effect of temperature on rate RATERATE TEMPERATURE What other factor caused the large rate increase between B and C More colliding particles have E Act 1 Time C B