Across
- 2. the study of living things
- 4. similar image
- 5. amount
- 7. elements combine to form new...
- 9. normal, everyday
- 11. a form of energy made by the movement of particles
- 13. similar poles repel, while opposite poles attract
- 16. unexpected
- 18. force that pulls everything toward it
- 19. the study of how the universe works
- 20. dirty marks
Down
- 1. disadvantage
- 3. occur all around us
- 6. something which can be used again
- 7. therefore
- 8. instruments, equipment
- 10. scientists have discovered 109 of these
- 12. almost completely
- 14. possibility
- 15. the study of what things are made of
- 16. the air all around us
- 17. small pieces
- 21. the building blocks of the universe