Across
- 3. plants breathe
- 6. Row on the periodic table with same number of atomic orbits
- 7. up pipes and wires
- 10. your swimming pool to kill bacteria
- 11. like rotten eggs
- 12. two metals combine
- 14. gas in a light bulb
- 15. makes up table salt
- 17. conductors of heat and electrici
Down
- 1. noble gas that makes your balloon float
- 2. Super reactive element in baking powder
- 4. breath this in to survive
- 5. up most of the earth's atmosphere
- 8. is made up of __________
- 9. up to 75% of all matter in the universe
- 13. column on the periodic table with same number of electrons
- 16. wrap your sandwich with this element