Across
- 2. can't make steel without it
- 4. needed to breathe
- 10. 1st place
- 12. makes up some of earth's crust
- 13. cans
- 14. odorless, tasteless, and colorless
- 15. very stinky
- 16. a planet
- 17. used in pools
- 18. 2nd place
Down
- 1. used for wiring
- 3. found in bananas
- 5. 1st on the periodic table
- 6. glows in the dark
- 7. type of battery
- 8. found in milk
- 9. antiseptic
- 11. used in balloons
- 16. atomic number 12
- 17. named after coal