Across
- 2. used to start a reaction
- 4. oil is mainly used for
- 5. energy-rich substances formed from the remains of organisms
- 10. 3 types of fossil fuels
- 11. energy created by the movement of the air
- 14. wood, plants parts, manure, and food wastes that can be used as fuels
- 15. percent of energy used to do work
- 19. what source is hydrogen fuel cells
- 21. a factory in which crude oil is heated and separated into fuels and other products
- 22. a chemical compound that contain hydro and carbon atoms
- 25. compounds that are made from crude oil
- 26. A layer of material that traps the air to help block the transfer of heat between the air inside the building
- 27. alchohol mixed with gasoline
- 28. heat from the earth's interior
Down
- 1. house that uses passive and active heating systems to get electricity and heat
- 3. 3 types of fossil fuels
- 6. an original source for wind and flowing energy
- 7. a nuclear reaction in which the nucleus forms up into a heavy nucleus
- 8. light and heat given off by the sun
- 9. save energy
- 12. fuels are burned, the chemical energy that is released can be used to generate another form of energy
- 13. a nuclear reaction in which the nucleus separates
- 16. coal is most used for
- 17. when uranium rods melt and explode
- 18. fossil fuels made in a long amount of time
- 20. electricity created by the power of moving water
- 23. a substance that provides energy
- 24. another name for oil