challenge it

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Across
  1. 3. when something changes forms(like marshmello over a fire)
  2. 5. release energy, usually in the forms of heat when the chemical bonds are broken
  3. 6. atoms that have been bonded together
  4. 8. transfer electrons between two or more atoms
Down
  1. 1. a group of atoms that are bonded together
  2. 2. links between atoms and a substance that determine its identity
  3. 3. share electrons between two or more atoms
  4. 4. negatively charged ion
  5. 6. positively charged ion
  6. 7. the simplest form of matter