Rates of reaction

• What can be plotted to show the rate of reaction?

  A graph of mass or volume of product formed against time
• How do you calculate the rate of reaction at a specific time from a graph?

  By drawing a tangent to the graph and calculating the gradient
• What is the minimum energy needed for a successful collision called?

  Activation energy
• What does collision theory state about reactant particles?

  They must collide with sufficient energy for a reaction to happen
• What happens to the rate of reaction when temperature increases?

  More particles have sufficient energy to react
• What can be plotted to show the rate of reaction?

  A graph of mass or volume of product formed against time
• How do you calculate the rate of reaction at a specific time from a graph?

  By drawing a tangent to the graph and calculating the gradient
• What does the gradient value represent in a reaction graph?

  The rate of reaction
• What does collision theory state about reactant particles?

  They must collide with sufficient energy for a reaction to happen
• What is the minimum energy needed for a reaction called?

  Activation energy
• How does increasing temperature affect the rate of reaction?

  It increases the rate of reaction
• Why does increasing temperature increase the rate of reaction?

  Because it leads to more frequent and successful collisions
• How does increasing concentration affect the rate of reaction?

  It increases the rate of reaction
• What is the effect of increasing surface area on the rate of reaction?

  It increases the rate of reaction
• How do catalysts affect the rate of a reaction?

  They increase the rate of a reaction
• What is a key characteristic of catalysts in chemical reactions?

  Catalysts are not used up during reactions
• How do catalysts work in a reaction?

  By providing an alternative pathway with lower activation energy
• What are enzymes classified as?

  Biological catalysts
• What is the definition of activation energy?

  The minimum energy needed for a reaction to happen
• What does concentration refer to in a solution?

  The amount of substance per unit volume of solution
• What does frequency refer to in the context of reactions?

  The number of times something occurs in a given time
• What is a gradient in the context of a graph?

  A straight line between two points on a curve
• What are reactants?

  Substances that take part in a reaction
• What are products in a chemical reaction?

  A substance formed in a chemical reaction
• What is a tangent in relation to a curve?

  A straight line that just touches a point on a curve
• What is the formula for calculating the rate of reaction?

  • Rate of reaction = quantity of product formed / time taken
• How can the changing rate of a reaction mixture be measured?

  • By measuring during the reaction
  • If a gas is produced or water is formed
  • Plotting the quantity of product formed against time
• How can the changing volume of a reaction mixture be monitored?

  • By measuring the volume during a reaction
  • Using appropriate equipment to track changes