Periodic Table Crossword.

1234567891011121314151617181920
Across
  1. 1. 20th element
  2. 3. 16th element
  3. 4. 14th element
  4. 8. 18th element
  5. 11. 9th element
  6. 12. 8th element
  7. 13. 17th element
  8. 14. 4th element
  9. 15. 3rd element
  10. 18. 15th element
  11. 20. 8th element
Down
  1. 2. 13th element
  2. 5. 6th element
  3. 6. 12th element
  4. 7. 19th element
  5. 9. 2nd element
  6. 10. 7th element
  7. 16. 1st element
  8. 17. 5th element
  9. 19. 11th element