Elements Crossword puzzle

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Across
  1. 6. is usually associated with bones and chalk but is firm in it's pure form
  2. 7. Atomic symbol is Na
  3. 8. atomic symbol is Fe
  4. 10. is a pale yellow gas
  5. 12. this group has Helium and Neon
  6. 13. also known as the chalcogens
  7. 15. pennies are made of this metal
  8. 16. Gas that takes up 21% of the atmosphere
  9. 18. are in group 1 of the periodic table
  10. 19. the lightest metal
  11. 20. This element's atomic symbol is Al
  12. 21. these are the rows of the periodic table
Down
  1. 1. Atomic symbol is H and is 1
  2. 2. are in group 17 of the periodic table
  3. 3. are apart of group 15 of the periodic table
  4. 4. this group is sometimes called the
  5. 5. are in group 2 of the periodic table
  6. 9. Atomic number is 36
  7. 11. Atomic symbol is C
  8. 14. these are the columns of the periodic table
  9. 17. this element is used clock and watch