Effect of Surface Area on Rate

• What is required for chemical reactions to occur according to collision theory?

  Reacting particles must collide with sufficient energy
• How is the rate of a chemical reaction determined?

  By the frequency of successful collisions
• What does the term frequency refer to in the context of chemical reactions?

  The number of successful collisions per second
• How does the surface area of a solid reactant affect the rate of a reaction?

  A greater surface area increases the rate of reaction
• What happens when a solid reactant is divided into smaller blocks?

  It increases the surface area available for reaction
• Why can only surface particles of a solid reactant react with particles in solution?

  Because only surface particles are accessible
• What is the relationship between surface area to volume ratio and reaction rate?

  Smaller blocks have a greater surface area to volume ratio
• What is a more accurate method to measure gas volume in a reaction?

  Using a gas syringe
• How can the mass of carbon dioxide gas be measured during a reaction?

  By placing the reaction on a balance
• What does the cotton-wool do in the experimental setup?

  Allows gas to escape while preventing acid splashes
• What can cause an anomalous result in the mass measurement during the reaction?

  Acid splashing out of the flask
• What is one way to investigate the effect of surface area on the rate of reaction?

  • Use marble chips with hydrochloric acid
  • Measure the volume of carbon dioxide produced
  • Change the surface area of the marble chips