science chap 5 and 6

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Across
  1. 2. energy the energy required to break a particular type of covalent bond.
  2. 3. take place the coliding particles must possess at least this amount of energy.
  3. 5. the thermal heat content of a system
  4. 7. the minimum energy required to start a chemical reaction for a reaction
  5. 9. a chemical reaction in which a subtance reacts oxygen the reaction is exothermic.
Down
  1. 1. the attachment of molecules to a solid surface.
  2. 4. a subtance that increases the rate of a chemical reaction but itself remains unchanged at the end of the reaction.
  3. 6. change a change in which a new subtance is formed.
  4. 8. theory a theory that states that a chemical reaction takes place when particles of the reactants collide with suffcient energy the reaction.