rates of reaction

• Rate of Reaction


  The speed at which a reaction takes place
• Measuring the rate of reaction


  1. Measure how quickly the reactants are used

  2. Measure how quickly the products are formed
• Methods to measure the rate of reaction

  • Change in mass
  • Volume of gas formed
  • Formation of a precipitate
  • Decrease in light intensity
• Collision Theory


  • For a reaction to happen, the reacting particles must successfully collide with sufficient energy
  • A successful collision is one that leads to a reaction happening
• Surface area


  • A larger surface area provides for more chances of successful collisions, increasing the rate of reaction
• Catalyst


  A substance that speeds up a reaction without being used up
• Increasing the rate of reaction

  Increases the chance/frequency of successful collisions
• Ways of changing the rate of a reaction

  • Temperature
  • Concentration
  • Surface area
  • Catalyst
• Temperature


  At a higher temperature, the particles move faster, increasing the chance of successful collisions and a faster rate of reaction
• Concentration


  Decreasing the concentration increases the number of reacting particles, increasing the chance of successful collisions and a faster rate of reaction
• Catalyst


  By lowering the activation energy, a catalyst increases the chance of successful collisions, leading to a faster rate of reaction
• A graph is used to follow the course of a reaction
• Comparing graphs shows the differences in the rates of similar reactions