p. 258, #1-10

1. Petroleum is sometimes called "buried sunshine" because the energy stored in petroleum originally came from the sun.

2.
a. potential energy: energy of position (ex. a ball on top of a steep hill)
b. kinetic energy: energy related to motion (ex. a child riding a bike)

3. During a chemical reaction, existing bonds are broken and new bonds are formed.

4. A molecule of butane has more potential energy because it has more carbons, which means that the molecule has more electrons.

5.
a) potential energy
b) potential energy
c) kinetic energy
d) potential energy
e) potential energy

6. Energy is required to break chemical bonds because it is needed to break preexisting bonds and reorganize to form new bonds. The products have less potential energy than they did before the chemical reaction took place.

7.
a) exothermic reaction
b) endothermic reaction
c) exothermic reaction

8. Burning of a candle gives off heat energy, therefore it is an exothermic reaction. The product has less energy than the original reactants because it has to give off its energy in order for the reaction to create fire.

9. See picture

10. The law of conservation of energy states that energy can not be created nor destroyed in any chemical, mechanical, or physical processes.