1 / 20

Module 3

Module 3. Lesson 11 – Catalysis. Objectives. Must State that a catalyst speed up the reaction but are not consumed during it. Should Describe how catalysts often requiring lower temperatures and reducing energy demand and CO2 emissions. Could

kaveri
Télécharger la présentation

Module 3

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. Module 3 Lesson 11 – Catalysis

  2. Objectives Must State that a catalyst speed up the reaction but are not consumed during it. Should Describe how catalysts often requiring lower temperatures and reducing energy demand and CO2 emissions. Could Explain the effect of the proportion of molecules possessing greater than or equal to activation energy on rate of reaction.

  3. Starter - Definitions Catalysts are substances which increase the rate of a chemical reaction without being consumed by it themselves. They do this by providing an alternative route for the reaction with a lower activation energy.

  4. Benefits of catalysts Describe and explain three potential benefits of using catalysts in an industrial process.

  5. Did you get? • Lower temperatures and pressures required therefore reducing energy demand. • Different reactions can be used with better atom economy thus reducing waste • Lower production costs • Catalysts can be used to generate specific products

  6. Maxwell-Boltzmann activation energy (catalysed) activation energy (uncatalysed) Eacat Ea

  7. The effect of temperature • We would expect rate to increase with increasing temperature because the number of collisions increases. • However, we also know that particles need a minimum amount of energy to react when they collide. We call this the ACTIVATION ENERGY. • If particles do not have enough energy when they collide they simply bounce off each other. • Increasing temperature gives the particles more energy and so more of them have enough energy to react when they collide.

  8. Enthalpy profiles Ea Ec ΔH products

  9. Past paper question

  10. Mark scheme

  11. Mark scheme

  12. Past Paper Question 7 marks

  13. Practical Demonstration • Decomposition of H2O2 with and without a catalyst (MnO2)

  14. Catalase in liver • Catalysts are often enzymes, generating very specific products and operating effectively close to room temperatures and pressures. • Demonstration or video http://www.youtube.com/watch?v=hR38o2Ec8b0 • Denaturing

  15. Plenary – industrial processes Catalysts have a wide range of crucial industrial applications. Ones you should be aware of include: • Iron in ammonia production • Ziegler Natta catalyst in poly(ethene) production • Platinum, palladium and rhodium in catalytic converters

  16. Examination question

  17. Mark scheme

More Related