Across
- 2. 30% of Earth crust
- 3. Toxic Gas
- 4. 20% of human bodies
- 8. need for healthy joints
- 9. colorless
- 11. lightest metal
- 13. 2% of earth's crust
- 16. Odorless
- 18. can float on water
- 19. discovered in 1791 forgotten and rediscovered
- 21. 100% recyclable
Down
- 1. not all of it's variations are metal
- 2. melts at 1410 c
- 4. has rich blue hue
- 5. can be found in pools
- 6. 25% of the nickel
- 7. essential for human nutrition
- 8. turns yellow/pink when exposed to air
- 10. 5th most abundant in Earth's crust
- 12. 90% of atoms
- 14. conductor
- 15. bugs die when they come in contact with it
- 17. highly reactive
- 20. used for scuba diving