1. Warm-Up November 24, 2014 What do you know about combustion and/or oxidation-reduction reactions? What do you know about combustion and/or oxidation-reduction reactions?

2. Objective SWBAT understand the chemistry of combustion and the three types of heat transfer. SWBAT understand the chemistry of combustion and the three types of heat transfer.

3. Agenda 1. Combustion 2. Oxidation-Reduction Reactions 3. Potential Energy Diagrams 4. Heat Transfer 5. Combustion at a Sugar Plant Article 6. Oklahoma City Bombing Documentary 7. Exit Slip

4. Combustion Reactions Combustion reactions occur when a hydrocarbon reacts with oxygen gas. This is also called burning!!! In order to burn something you need the 3 things in the “fire triangle”: 1) A Fuel (hydrocarbon) 2) Oxygen to burn it with 3) Something to ignite the reaction (spark)

5. Combustion Reactions In general: C x H y + O 2  CO 2 + H 2 O Products in combustion are ALWAYS carbon dioxide and water. (although incomplete burning does cause some by- products like carbon monoxide) Combustion is used to heat homes and run automobiles (octane, as in gasoline, is C 8 H 18 )

6. Combustion Reactions Edgar Allen Poe’s drooping eyes and mouth are potential signs of CO poisoning.

7. Combustion Example C 5 H 12 + O 2  CO 2 + H 2 O Write the products and balance the following combustion reaction: C 10 H 22 + O 2  5 6 8

8. Oxidation-Reduction Reactions https://www.youtube.com/watch?v=lQ6FB A1HM3s https://www.youtube.com/watch?v=lQ6FB A1HM3s https://www.youtube.com/watch?v=lQ6FB A1HM3s https://www.youtube.com/watch?v=lQ6FB A1HM3s

9. Potential Energy Diagrams ► Activation Energy is the amount of energy to start a reaction or the energy needed so that the reactants bonds will break and reform to make product Activation Energy Activation Energy

10. Exothermic Reactions ► Release heat ► Reactants Ep is higher than Products Ep. ► Combustion reactions are exothermic

11. Three methods of heat transfer…

12. Three Heat Transfer Methods Conduction: Conduction is the only means of transferring heat to the interior of fuels (wood, litter, duff). High-density fuels (green wood) vs. low-density fuels (litter, decayed wood) High density fuels have greater conductivity – more heat needed to raise temperature of surface layer Transfer of heat from one molecule to another. Example: touching your hand to a hot object

13. Radiation: Transmission of heat by electromagnetic waves. Examples of radiation:Heat from sun, fire place, stove Contact between radiation source and affected body not necessary Example: preheating of fuels ahead of fire front Absorption of radiation by woody fuels – only by thin layer at surface (rest by conduction)

14. Convection: Transfer of heat by movement of a gas or liquid (air). Hot air moves vertically (exceptions: winds, slopes) Examples: heating a pot of water, smoke from a fire.

15. What Factors can Increase Heat Transfer?

16. Flames are brought closer to the fuel due to slope. Factors that Increase Heat Transfer

17. Wind The wind pushes the flames over......bringing the flames closer to the fuel.

18. Heat Transfer Video & Song http://video.search.yahoo.com/video/play;_ylt=A2 KLqIL.JM5RpU8A5lD7w8QF;_ylu=X3oDMTB2MWN mYzNpBHNlYwNzcgRzbGsDdmlkBHZ0aWQDVjEzM QRncG9zAzc- ?p=convection%2C+conduction%2C+radiation&vi d=bc23b19f58302e316cced7db9ef2c3e3&l=2%3A 44&turl=http%3A%2F%2Fts3.mm.bing.net%2Fth %3Fid%3DV.4529675467229482%26pid%3D15.1 &rurl=http%3A%2F%2Fwww.youtube.com%2Fwa tch%3Fv%3DenrsfHG5eB8&tit=Conduction+conve ction+radiation%3A+Heat+transfer&c=6&sigr=11 afno5c7&age=0&fr=my-myy&tt=b http://video.search.yahoo.com/video/play;_ylt=A2 KLqIL.JM5RpU8A5lD7w8QF;_ylu=X3oDMTB2MWN mYzNpBHNlYwNzcgRzbGsDdmlkBHZ0aWQDVjEzM QRncG9zAzc- ?p=convection%2C+conduction%2C+radiation&vi d=bc23b19f58302e316cced7db9ef2c3e3&l=2%3A 44&turl=http%3A%2F%2Fts3.mm.bing.net%2Fth %3Fid%3DV.4529675467229482%26pid%3D15.1 &rurl=http%3A%2F%2Fwww.youtube.com%2Fwa tch%3Fv%3DenrsfHG5eB8&tit=Conduction+conve ction+radiation%3A+Heat+transfer&c=6&sigr=11 afno5c7&age=0&fr=my-myy&tt=b http://video.search.yahoo.com/video/play;_ylt=A2 KLqIL.JM5RpU8A5lD7w8QF;_ylu=X3oDMTB2MWN mYzNpBHNlYwNzcgRzbGsDdmlkBHZ0aWQDVjEzM QRncG9zAzc- ?p=convection%2C+conduction%2C+radiation&vi d=bc23b19f58302e316cced7db9ef2c3e3&l=2%3A 44&turl=http%3A%2F%2Fts3.mm.bing.net%2Fth %3Fid%3DV.4529675467229482%26pid%3D15.1 &rurl=http%3A%2F%2Fwww.youtube.com%2Fwa tch%3Fv%3DenrsfHG5eB8&tit=Conduction+conve ction+radiation%3A+Heat+transfer&c=6&sigr=11 afno5c7&age=0&fr=my-myy&tt=b http://video.search.yahoo.com/video/play;_ylt=A2 KLqIL.JM5RpU8A5lD7w8QF;_ylu=X3oDMTB2MWN mYzNpBHNlYwNzcgRzbGsDdmlkBHZ0aWQDVjEzM QRncG9zAzc- ?p=convection%2C+conduction%2C+radiation&vi d=bc23b19f58302e316cced7db9ef2c3e3&l=2%3A 44&turl=http%3A%2F%2Fts3.mm.bing.net%2Fth %3Fid%3DV.4529675467229482%26pid%3D15.1 &rurl=http%3A%2F%2Fwww.youtube.com%2Fwa tch%3Fv%3DenrsfHG5eB8&tit=Conduction+conve ction+radiation%3A+Heat+transfer&c=6&sigr=11 afno5c7&age=0&fr=my-myy&tt=b

19. Combustion at Sugar Plant Article Read and write a 3 full sentence summary. Read and write a 3 full sentence summary.

20. OKC Bombings Documentary 1. What is the conspiracy of the Oklahoma City bombings? 2. What does the former CIA director Woosley think the conspiracy involves? 3. What were the first leads that came out and what did eyewitnesses report? 4. What information did they get from where the truck was rented? 5. How did they conclude that John Doe 1 was Timothy McVey?

21. Homework Read Chapter 12, pgs. 434-443, Review #18-25 Read Chapter 12, pgs. 434-443, Review #18-25

22. Exit Slip November 24, 2014 Go to m.socrative.com and enter 417101 Go to m.socrative.com and enter 417101 Question: Name one of the types of heat transfer and give a real world example. Question: Name one of the types of heat transfer and give a real world example.