1. Energy and Fossil Fuels
Petroleum Section B

2. Energy and Fossil Fuels
Formed from pressure, heat and microbes
Buried plants and animals converted into energy source
Examples: Petroleum, natural gas and coal

3. Types of Energy and Conversions
Potential
Kinetic
Chemical
Mechanical
Thermal

4. Types of Energy and Conversions
Follows the Law of Conservation of Energy
Energy not created or destroyed but can be converted from one form to another

5. Types of Energy and Conversions
Potential
Stored energy
Coiled spring
Kinetic
Energy of movement
When spring is releasede

6. Types of Energy and Conversions
Chemical Energy
Also considered to be potential
Energy is stored in the bonds of the chemicals

7. Types of Energy and Conversions
Two steps to this reaction
1st- break bonds- requires energy
endothermic
2nd –new bonds form- releases energy
exothermic

8. Types of Energy and Conversions
Energy Diagram of a Chemical Reaction

9. Energy Efficiency No energy conversion is totally efficient
“Loss” of energy to surroundings
This is heat given off that cannot do work

10. Energy Efficiency

11. Ways to Calculate Energy
Specific heat capacity
Amount of energy required to raise one gram of a substance by 1 °C.
Measured in calories or joules
Water- high heat capacity J/g °C

12. Ways to Calculate Energy
Specific heat equation
Q= mcΔT
Q= energy
m= mass
C= specific heat
ΔT= change in temperature

13. Ways to Calculate Energy
Let’s try a problem
A piece of copper alloy with a mass of 85.0 grams is heated from 30 °C to 45 °C. In the process , how much energy does it absorb if its specific heat is .41 J/g °C?

14. Ways to Calculate Energy
You try one:
How much energy is needed to heat water from °C to 99 °C? The specific heat of water is J/g °C.

15. Ways to Calculate Energy
Heats of Combustion
Amount of heat energy given off when a substance burns
Expressed as kilojoules per mole (kJ/mol)

16. Ways to Calculate Energy
For example: When propane burns it gives off 2200 kJ/mol.
Combustion Reaction for propane:
Do the math:

17. Ways to Calculate Energy
You try: If ethane gives off 1560 kJ/mol, complete the combustion reaction and calculate how much energy is given off.