Rates of reaction

• How can you follow the progress of a reaction?


  By measuring the change in mass/measuring change in volume and by measuring other quantities (e.g. rate of effervescence)
• What effect does the change of temperature have on a reaction?


  At a higher temperature, particles have more energy. This means they move faster and are more likely to collide with other particles. When particles do collide they do so with more energy and so the number of successful collisions increase.
• What effect on the reaction speed does changing the concentration of a reactant have?


  At a higher concentration, there are more particles in the same amount of space. This means that particles are more likely to collide and therefore more likely to react.
• Describe the effect of particle size/surface area on rection speed.


  If the surface area increases there is an increased area for the reactant particles to collide with meaning a slower reaction speed. The smaller the pieces, the larger the surface area. This means more collisions and a greater chance of reaction.
• What is the effect of using a catalyst on a reaction?


  Catalysts speed up a reaction without getting used up or producing more product.
• What is the formula for figuring out the rate of reaction?


  ∆quantity/∆t
• Examples of slow reactions

  • Rusting
  • Formation of fossil fuels
• Examples of fast reactions

  • Explosions
  • Fireworks
  • Striking a match