Energetics

• What is rate of reaction??

  The rate of reaction is the speed at which the reactants are changed

  into the products.
• How do chemical reactions occur??

  Chemical reactions can only occur when reacting particles collide with

  each other.
• What name is given to the minimum amount of energy needed by

  particles for them to react when they collide?

  Activation energy
• What are the 4 factors affecting the rate of reaction? :

  • temperature
  • concentration
  • particle size
  • use of a catalyst
• A chemical reaction will happen faster if a solid is broken into smaller

  pieces because the surface area is larger
• Catalytic converters :

  • Catalytic converters are found in the exhaust systems of

  vehicles like cars.

  • They speed up useful chemical reactions which reduce

  the pollution released by the vehicle.
• Catalysts :

  • Catalysts are substances that speed up a chemical reaction

  without being used up in the reaction.

  • Catalysts never produce more product – they just

  produce the same amount more quickly.
• Everyday catalysts :

  • Nickel is a catalyst in the production of margarine

  (hydrogenation of vegetable oils).

  • Iron is a catalyst in the production of ammonia from nitrogen and hydrogen (the Haber process).
  • Platinum is a catalyst in the catalytic converters of car exhausts. It catalyzes the conversion of carbon monoxide and nitrogen oxide
  • into the less polluting carbon dioxide and nitrogen.