50 Days Until the Harvard Westlake Final

1. 50 Days Until the Harvard Westlake Final Catalyst: • I increase the concentration of reactants, will the rate of my reaction increase or decrease? Why? • I decrease the temperature will the rate increase or decrease? Why? 3. Define rate of reaction. End

2. Reading Debrief • What is decomposition? • Why don’t McDonalds fries or burgers decompose? • How can we slow the rate at which something decomposes? • Should we be adding chemicals to our foods in order to preserve them? • What other questions did you have during this reading?

3. Post-Lab Analysis

4. LECTURE 8.2 – CATALYSTS, ACTIVATION ENERGY, AND REACTION COORDINATES

5. Elephant Toothpaste

7. Today’s Learning Targets • LT 8.4 – I can explain what the activation energy of a reaction is. I can identify it on a reaction coordinate and explain how it influences the rate of a reaction. • LT 8.5 – I can define what a catalyst is and explain how it is related to the rate of chemical reaction. I can explain how a catalyst is related to a reactions activation energy.

8. Today’s Focus Question • How could we speed up the rate at which McDonald’s French Fries decompose?

9. What are reaction coordinates?

10. I. Reaction Coordinate • We can graph the energy that is associated with a reaction using a reaction coordinate. • This can indicate exothermic and endothermic reactions by highlighting the change in energy. Reactants Products

11. II. Activation Energy • Reactions require a certain amount of energy in order to proceed. • Activation Energy– The amount of energy required to get the reaction to go to completion.

13. Activation Energy Reactants Products

14. Quick Check • Which diagram has a lower activation energy?

15. What are catalysts?

16. I. Catalyst • Acatalystis substance that speeds up the rate of reaction by lowering the activation energy. • Speeds up the reaction without using up the catalyst. Ea without catalyst Ea with catalyst

18. II. Catalysts and Activation Energy • The energy difference remains exactly the same. The only change is that less energy is required for the reaction to proceed.

19. Quick Check • Which reaction diagram shows the effect of using the appropriate catalyst in a chemical reaction?

20. Use the following words: • Accelerate • Catalyst • Activation Energy • Reaction Coordinate Summarize

21. Catalyst Lab Introduction • A catalyst is anything that speeds up the rate of a chemical reaction. • Today we will be examining the impact of catalysts on rates of H2O2 decomposition.

22. Catalyst Lab • Re-read through the lab handout. • Compare the lab instructions to the lab checklist.

23. Catalyst Foundations • Catalyst Foundations and Lab Guide • Create reaction coordinate graphs and analyze data.

24. Draw Something • Let’s do some vocab review! • Draw the picture that best represents these terms: • Rate • Activation Energy • Catalyst • Reaction Coordinate • Concentration • Collisions

25. Expected Outcomes • You will complete the lab as one group. • Roles of Group Members: • Yeast Trials -Don’t pipet yeast, use graduated cylinder • Carrot Trial • Tomato Trials (3 mL) -Don’t pipet tomato, use graduated cylinder • Filmer/Note Taker • At the end of the lab complete the group assessment questions 1-3

26. Lab Work Time

27. Enrichment • Too easy? Learning Logs all 4’s? • Try out some enrichment • Practice with 2011 ACS Chemistry Olympiad Tests • Practice with collision theory: 8.2.AP.CollisionTheory • Practice with reaction rates: 8.2.AP.ReactionRates

28. Lab Debrief • Answer all of the post-lab questions.

29. Exit Ticket 1. Draw a general reaction coordinate. Label reactants, products, and activation energy 2. On the reaction coordinate that you drew, draw a dashed line to represent how a catalyst would impact the coordinate.

31. Closing Time • Lab Report Due Feb. 27th!