Element crossword puzzle

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Across
  1. 2. Makes up most of Earth's atmosphere
  2. 5. Lightweight, corrosion-resistant metal
  3. 6. Basis of all known life
  4. 8. Light metal used in batteries
  5. 9. Component of DNA and fertilizers
  6. 13. Lightest element, makes up most of the universe
  7. 14. Noble gas used in balloons
  8. 16. Element in borax and used in detergents
  9. 17. Lightweight metal used in fireworks
  10. 19. Essential nutrient for plants and humans
Down
  1. 1. Found in computer chips and sand
  2. 3. Noble gas used in signs
  3. 4. Essential for bones and teeth
  4. 7. Used to disinfect water
  5. 10. Essential for respiration
  6. 11. Strong, lightweight metal used in aerospace
  7. 12. Highly reactive halogen
  8. 15. Common reactive metal, used in table salt
  9. 18. Yellow nonmetal used in matches
  10. 20. Noble gas used in light bulbs