Lab

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Across
  1. 5. a formula
  2. 7. when bonds give off heat
  3. 8. the transferring of atoms
  4. 10. links between atoms in a substance
Down
  1. 1. requires energy to occur
  2. 2. when something changes physically
  3. 3. a group of atoms
  4. 4. building block if matter
  5. 6. becomes positively charged
  6. 9. the sharing of valence electrons