Beginner's Luck (Easy)

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Across
  1. 3. Element number 16
  2. 7. Atomic linkage
  3. 9. Temperature unit
  4. 10. Chlorine or bromine
  5. 11. Pressure unit
  6. 14. Chemical equation species
  7. 15. _______ flask
  8. 17. Reaction accelerant
  9. 18. Shell
  10. 19. Not neutral
  11. 20. Wave period
  12. 21. Solute + solvent
Down
  1. 1. Proton acceptor
  2. 2. Seven
  3. 4. 6.02x10^23
  4. 5. Type of gas
  5. 6. On target
  6. 8. Radioactive elements
  7. 10. Type of mixture
  8. 12. Phase change
  9. 13. Concentration unit
  10. 16. Heat unit