Across
- 4. greenhouse gas
- 5. benzene
- 7. going same speed in both directions
- 9. rust
- 10. CH4
- 12. methane
- 15. C6H6
- 16. alternating single and double bonds with high stability
- 18. contains carbon and hydrogen
- 19. two atoms getting together
- 20. how atoms combine
Down
- 1. negative charge in atom
- 2. how fast an atom holds its electrons
- 3. used in batteries
- 6. Fe2O3
- 8. really large number of atoms or molecules
- 11. study of rates of reactions
- 13. first element
- 14. makes balloons stay up
- 17. makes reaction faster without getting used up