Rates of reaction

2.2 Related calculations

2.4 Energy changes

Rates of reaction

  1. Definition

    1. The rate of a reaction can be calculated by measuring the amount of reactant used or product formed over time
    2. A graph showing the amount of a reactant used or product formed over time has the rate of reaction as the gradient1

  2. Collision theory

    1. Chemical reactions can only occur when reacting particles collide with each other with sufficient energy
    2. The activation energy of a reaction is the minimum amount of energy required for the particles of the reaction to react

  3. Factors increasing rates of reaction

    1. Increasing the temperature increases the speed of the reacting particles so they collide more frequently & energetically
    2. Increasing the pressure of gaseous reactants increases the frequency of collisions
    3. Increasing the concentration of aqueous reactants increases the frequency of collisions
    4. Increasing the surface area of solid reactants increases the frequency of collisions
    5. Catalysts increase the rate of reaction without being expended; different reactions require different catalysts
    6. Catalysts are important in reducing the cost of industrial processes
  1. More accurately: the derivative ↩