Hannah Downes' crossword puzzle.

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Across
  1. 2. something that gets reacted with
  2. 4. smallest unit of matter
  3. 7. two or more atoms connected
  4. 11. coming together
  5. 13. mixing chemicals
  6. 15. realizing heat
Down
  1. 1. gaining heat
  2. 3. something made of chemicals
  3. 5. the weight of matter
  4. 6. something that happens when chemicals mix
  5. 8. shown on the periodic table
  6. 9. the thing chemicals make
  7. 10. made up of molecules
  8. 12. the ability to do work
  9. 14. when you hot