Across
- 2. A radioactive element used in nuclear power
- 4. The most reactive halogen
- 6. Makes up 78% of Earth’s atmosphere
- 11. Found in emeralds
- 13. Used in balloons
- 14. The basis of organic life
Down
- 1. A metal used in electrical wiring
- 3. A lightweight metal used in cans
- 5. A noble gas used in signs
- 7. A transition metal found in hemoglobin
- 8. Essential for respiration
- 9. A precious metal resistant to tarnish
- 10. An alkali metal used in batteries
- 12. A metalloid used in semiconductors
- 13. The lightest element