casper
Uploaded by
30 SLIDES
446 VIEWS
300LIKES

Understanding the Role of Catalysts in the Conversion of Cis-2-Butene to Trans-2-Butene

DESCRIPTION

This lesson focuses on the kinetics of the conversion of cis-2-butene to trans-2-butene, emphasizing the role of catalysts in speeding up this reaction. We will explore the step-by-step mechanism involving iodine (I2) as a catalyst. The process begins with the dissociation of I2, followed by its attachment to the carbon atom, breaking the double bond, and allowing rotation before reforming a double bond and removing iodine. Understanding these steps sheds light on the catalytic process and its significance in chemical reactions.

1 / 30

Download Presentation

Understanding the Role of Catalysts in the Conversion of Cis-2-Butene to Trans-2-Butene

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Unit 7: Kinetics Microscale Kinetics Day 2

  2. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene

  3. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates

  4. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates

  5. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates

  6. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates

  7. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates

  8. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone

  9. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Intermediate

  10. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate

  11. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate

  12. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate

  13. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate

  14. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate

  15. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate

  16. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms

  17. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  18. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  19. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  20. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  21. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  22. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  23. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  24. Unit 7: Kinetics More on Catalysts Catalysts speed up reaction rates, how? cis-2-butene converts to trans-2-butene I2 Cis-2-butene Step 1: I2 dissociates Step 2: I attaches to C breaking the double bone Catalyst Step 3: Single bond is now free to rotate Intermediate Step 4: Iodine is removed and double bond reforms Product

  25. Unit 7: Kinetics Reaction Mechanisms: The sequence of bond-making and bond breaking steps that occur during a reaction. Refer back to the cis to trans conversion of butene… I2

  26. Unit 7: Kinetics Reaction Mechanisms: The sequence of bond-making and bond breaking steps that occur during a reaction. Br2 + 2 NO  2 BrNO What would it take for this to be a single step reaction??? (Think collision theory) Br2 NO NO Since this is unlikely, the following mechanism is proposed …

  27. Unit 7: Kinetics Molecularity of Mechanism Steps: The decomposition of ozone: 2 O3 3 O2 Termolecular and beyond:

  28. Unit 7: Kinetics Rates of Mechanism Steps: Each individual step has its own rate, and therefore its own rate law. Stoichiometry can only be used to write rate laws for mechanism steps!!! (NOT OVERALL REACTIONS)

  29. Unit 7: Kinetics Practice Problem: 3 ClO- ClO3- + 2Cl- Proposed mechanism: Step 1: Pt + 2 ClO- PtClO2-+ Cl- Step 2: PtClO2- + ClO- Pt + ClO3- + Cl- a. What is the molecularity of each step? b. Write the rate equation for each step? c. Show that the sum of the steps gives the overall reaction. d. Identify any catalysts and/or intermediates present.

  30. Unit 7: Kinetics Sample AP Multiple Choice: The energy diagram for R  P is shown above. The addition of a catalyst to this reaction would cause a change in which of the indicated energy differences? I II III • I only • II only • III only • I and II only • I, II and III

More Related