(Chemical Reaction) Crossword(5)

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Across
  1. 4. properties that can be observed without changing its identity
  2. 6. properties that can be observed as it reacts with other substances
  3. 8. when a fuel burns in oxygen and produces C02,H20 and thermal energy
  4. 9. substances that react at the start of a reaction
  5. 10. anything that has mass and volume
Down
  1. 1. uses chemical formulas and symbols to describe a chemical reaction
  2. 2. when 2 or more substances combine and form a complex substance
  3. 3. when 1 substance breaks down into 2 or more substances
  4. 5. number in front of the formula that tells us how many molecules are present
  5. 7. substances formed at the end of a reaction