Chemistry

123456789101112131415161718192021222324252627282930
Across
  1. 3. major component of atmosphere
  2. 4. period number of erbium
  3. 6. d and f blocks
  4. 8. abundant metal in meteorites
  5. 9. hydrogen-3
  6. 11. not a dime
  7. 13. major bone constituent
  8. 15. 79 protons
  9. 16. protons plus neutrons
  10. 18. alkaline earth
  11. 19. silliest element
  12. 20. high energy light rays
  13. 22. invented periodic table
  14. 24. found in electrical wire
  15. 26. where protons are found
  16. 27. pencil lead
  17. 29. equals atomic number
  18. 30. inert gas
Down
  1. 1. positive electron
  2. 2. occurs at regular intervals
  3. 5. unreactive
  4. 7. unstable nucleus
  5. 10. last naturally-occurring element
  6. 12. helium-4 nucleus
  7. 14. same protons different neutrons
  8. 17. where elements are made
  9. 19. alkali metal
  10. 20. periodic table columns
  11. 21. conducts electricity
  12. 23. part of scientific notation
  13. 25. neutral charged particle
  14. 28. halogen