1 / 35

Chapter 3.B. Petroleum: An Energy Source

Chapter 3.B. Petroleum: An Energy Source. Do Now. Read Chem Quandary #1 on page 237 Answer questions: a, b, and c. Objectives. 1. SWBAT define kinetic, potential, chemical, thermal, endothermic, exothermic and energy conversions. 2. SWBAT state the law of conservation of energy.

hal
Download Presentation

Chapter 3.B. Petroleum: An Energy Source

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. Chapter 3.B. Petroleum: An Energy Source

  2. Do Now • Read Chem Quandary #1 on page 237 • Answer questions: a, b, and c

  3. Objectives • 1. SWBAT define kinetic, potential, chemical, thermal, endothermic, exothermic and energy conversions. • 2. SWBAT state the law of conservation of energy.

  4. B.1. Energy and Fossil Fuels • Petroleum: remains of prehistoric plants and animals • Fossil Fuels: petroleum, natural gas, and coal (buried sunshine) • 500 million years ago – living matter died and became covered by sediments • Through pressure, heat, and microbes – became petroleum • NON RENEWABLE RESOURCE

  5. Energy • Energy: Ability to do work • A. Potential Energy- stored energy (energy of position) • B. Kinetic Energy – motion • C. Chemical Energy- stored in chemical bonds • D. Thermal Energy- heat

  6. Think-Pair-Share • What type of energy? • 1. Petroleum • 2. Boiling Water • 3. Running • 4. Compressed Spring • 5. Natural Gas • 6. Rock Rolling Down a Hill

  7. Combustion • Burning of methane • In order for a chemical reaction to happen we must break bonds and build different bonds. CH4 + 2O2 CO2 + 2H2O + energy

  8. Types of Reactions • Endothermic; requires a net input of energy (reactants) • Exothermic: requires a net output of energy (products)

  9. If a reaction is exothermic, then the reverse is endothermic • EX. • 2H2 + O2 2H2O + O2 + Energy VS. Energy + O2 + 2H2O 2H2 + O2

  10. B.2 Energy Conversions Fig. B Fig. C Fig. A Fig. D Fig. E

  11. Law of Conservation of Energy • Energy is not used up or lost – just changes form • EX. Potential to Kinetic

  12. Think-Pair-Share • Turn to pg. 243 and do #1-2

  13. Homework • Pg. 258# 1-3, 5, 7-12

  14. Do Now • Write down the types of energy involved in each conversion • A. Pencil falling off a desk • B. Hair Dryer • C. Eating a Sandwich • D. Car Driving

  15. Objectives • 1. SWBAT explain why energy conversions are never 100% efficient and calculate the cost associated with various energy conversions. • 2. SWBAT define heat of combustion and use it in various calculations, and explain why thermal energy produced per gram is a primary factor in choosing types of hydrocarbons for burning

  16. B.4. Energy Efficiency • Need to increase efficiency of energy transfers. (energy “lost” as heat) • Solar Cells: Solar energy to electrical energy • Fuel Cells: chemical energy to electrical energy

  17. B.5. Energy Conversion Efficiency • Problem: Assume that your family drives 225 mile each week and that car can travel 23.0 miles on one gallon of gasoline. How much gasoline does that car use in one year? • 225 mi23.0 mi • 1 wk 1 gal

  18. Think-Pair-Share • Turn to pg. 245 and answer questions #1-4 with a partner.

  19. B.6 Combustion Lab pg. 248 Alkane + _O2 _CO2 + _H2O + thermal energy

  20. B.7. Using Heats of Combustions 2C2H6 + 7O2 4CO2 + 6H2O + ? thermal energy 2C2H6 + 7O2 4CO2 + 6H2O + 3120 kJ Table 3.6 pg. 250

  21. Do Now • Assume the molar heat of combustion of carbon contained in coal is 394 kJ/mol C. • 1. Write a chemical equation for the combustion of coal (include thermal energy).

  22. Objectives • 1. SWBAT describe and explain why and give examples of 4 ways that chemists alter fuels: cracking, octane rating, oxygenated fuels, and lead based additives • 2. SWBAT to answer sample conversion problems.

  23. Sample Problem • How much energy (in kilojoules) is released by burning of 25 mol hexane?

  24. Think-Pair-Share • Turn to pg. 253 and do #1, 2a, 3a

  25. Worksheet

  26. Do Now • How much thermal energy is released from a reaction that has 15 mol of pentane? • 2. How much thermal energy is released from a reaction of 20 grams of butane?

  27. B.9 Altering Fuels • Chemists have been altering fuels to increase needs of consumers. • 1. Cracking: • Takes large hydrocarbons and breaks them down into smaller, more useable ones • Use of a catalyst • Ex. kerosene to gasoline C16H34 C8H18 C8H18

  28. 2. Octane Rating • Gasoline can burn prematurely in the cylinders of the engine (knocking or pinging) • Isooctane has excellent combustion properties

  29. 2. Octane Rating • Octane Rating: fuels burning efficiency • Higher the octane rating the better the less knocking • Usually an average between running engine and one with a load (passengers) • Isooctane has octane rating of 100 and straight chain heptane has zero.

  30. 2. Octane Rating • Back in the 1920s-1970s, (C2H4) 4Pb was added to straight chain gasoline to increase efficiency (leaded fuel) • MTBE: (methyl tetriary-butyl ether) contaimnation of water supply

  31. 3. Oxygenated Fuels • Blended gasoline to increase octane rating (additives that contain oxygen) • Less energy per gallon but have more efficient burning with less pollutants. • Ex. Methanol can be added.

  32. 3. Oxygenated Fuels • Isomerization: converting straight chains to branched

  33. Think-Pair-Share • To start to think about your end of unit project complete the following: • Pg. 257 #1-6

More Related