Across
- 2. salt is composed of
- 3. some pools have
- 6. number of 16
- 7. a soft silver white metal
- 10. in lamps and signs
- 17. number of 4
- 18. 2 valence electrons
- 19. to make glue
- 20. that is important in body functions
Down
- 1. formation of bones and teeth
- 4. symbol is Ar
- 5. is Al
- 8. flammable gas
- 9. number is 9
- 11. we breathe
- 12. up 78 percent of the earths atmosphere
- 13. what we put in balloons so they can go up
- 14. an atomic number of six
- 15. 2,3 electrons per shell
- 16. has this