1. Collision Theory Factors affecting rate Investigate how concentration 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. Collisions & Activation Energy Next slide

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

5. Effect of concentration on rate Increasing concentration increases the rate By increasing the number of collisions

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 concentration on reaction rate ++ S + SO 2

7. To investigate the effect of concentration 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 Repeat with different concentrations of Na 2 S 2 O 3 Inverse the time to get the rate

8. Effect of concentration on rate RATERATE CONCENTRATION Conclusion ? Rate is directly proportional to concentration 1 Time