Rate of chemical change

• How can rate of reaction be determined through product, when there is a solid reactant and gaseous product

  Gas collection - measure volume of gas produced in a gas syringe
• How can rate of reaction be determined through the reactant, when there is a solid reactant and a gaseous product

  Carry out reaction on a set of weighing scales and measure the loss of reactant mass over time
• Instrument used to record values at given time intervals during an experiment to determine rate of reaction

  Data logger
• Effect of change in temperature on the rate of reaction

  Increase in rate if reaction
• Effect if change in concentration or pressure on rate of reaction

  Increases rate of reaction
• Effect of change in surface area on the rate of reaction

  Increases rate of reaction
• Using particle theory explain effect of temperature change on rate of reaction

  . Increasing temperature gives particles more kinetic energy

  . They collide more frequently and collisions have more energy

  . Activation energy is more likely to be reached
• Using particle theory, explaining the effect of a change in concentration on rate of reaction

  . Increases the frequency of collision as there are more reactant particles occupying the same volume
• Using the particle theory, explain effect of a change in pressure on rate of reaction

  . Increases frequency of collisions as the reactant particles are closer together
• Using the particle theory, explain effect of a change in surface area on rate of reaction

  More of the reactant particles are exposed and available to react, so the frequency of collision increases.
• What is a catalyst

  Substances that speed up reactions without being changed or used up
• How do catalysts work

  . Catalysts decrease the activation energy

  . This increases the proportion of particles with sufficient energy to react
• What are enzymes

  Biological catalysts which catalyse particular reactions under particular conditions with regards pH and temperature
• Uses of enzymes


  Found in washing detergents

  Used in manufacture of cheese