Across
- 3. Electrical energy produced by falling water.
- 4. The transport of energy by surface ocean waves.
- 6. Energy transfer by contact or touch.
- 8. Energy transfer by circulation.
- 10. The energy produced by heat within the Earth.
- 11. A mixture of gaseous hydrocarbons located under the surface of the Earth formed mainly of decayed sea organisms.
- 13. A solid fossil fuel that forms underground from partially decomposed plant material.
- 14. The energy received by the Earth from the Sun in the form of radiation.
- 15. Organic (once living) matter that can be a source of energy.
- 16. When the amount of energy received from the Sun and the amount of energy returned to space are about equal.
- 17. Any natural material that is used by humans.
Down
- 1. Uses Uranium (nonrenewable) to produce heat and steam to make the reaction work.
- 2. The process of recovering valuable or useful materials from waste or scrap and reusing it.
- 5. The use of a windmill to drive an electric generator.
- 6. The energy released when a chemical compound reacts to produce new compounds.
- 7. Resources that forms at a rate that is much slower than the rate at which we consume or use it.
- 9. A liquid mixture of complex hydrocarbon coumpounds formed mainly from decayed sea organisms.
- 12. A mixture of gasoline and alcohol that is used as a fuel.
- 14. A photochemical base that forms when sunlight acts on industrial pollutants and burning fossil fuels.