Question 1: Define 'surface area' in the context of a chemical reaction.

Answer: Surface area is the total area of the exposed surface of a solid substance that is available for a chemical reaction.

Question 2: Explain how increasing the surface area of a reactant affects the rate of a chemical reaction.

Answer: Increasing the surface area exposes more particles to react, which generally increases the reaction rate.

Question 3: Describe a real-world example where surface area impacts performance in sports science.

Answer: The design of sports equipment like cricket balls with textured surfaces or athlete's clothing with microfibres to increase surface contact can influence performance by affecting reaction or friction rates.

Question 1: A piece of aluminium foil measures 10 cm by 10 cm and has a thickness of 0.1 mm. Calculate its total surface area in square metres.

Answer: 0.02

Question 2: If doubling the surface area of a reactant doubles the rate of reaction, by what factor does tripling the surface area increase the rate?

Answer: 3

Question 1: Describe a simple experimental setup to investigate how surface area affects the rate of a chemical reaction involving a solid reactant.

Answer: Use different sizes of the same solid reactant (e.g., powder, small pieces, large chunks) placed in identical conditions with a common liquid reactant. Measure the reaction rate by observing changes such as gas production or colour change, ensuring safety precautions like wearing gloves and eye protection are followed.

Question 2: Identify two variables that must be controlled in this experiment and explain why.

Answer: Temperature and concentration must be controlled because changes in these can also affect reaction rate, making it difficult to isolate the effect of surface area.

Question 1: In an experiment, a powdered form of a reactant produced twice the amount of product in half the time compared to the same mass of large chunks. What does this suggest about the effect of surface area?

Answer: It suggests that increasing surface area by powdering the reactant increases the reaction rate, as more particles are exposed for reaction.

Question 1: Discuss how increasing the surface area of a sports equipment component, such as a tennis ball with textured surface, can influence its performance during a game. Include scientific reasoning in your answer. (6 marks)

Answer: Increasing the surface area of a tennis ball's textured surface enhances air friction and grip, improving control and spin. Scientifically, a larger surface contact area can also influence the air resistance acting on the ball, potentially affecting its speed and trajectory during play.

Question 1: Provide an example of how increasing surface area has been utilised in sports equipment or clothing to enhance athlete performance or safety, and explain the scientific principle behind it.

Answer: Microfibre clothing increases surface contact with air and sweat, improving cooling and comfort. The increased surface area facilitates better heat dissipation and moisture evaporation, which can help athletes maintain optimal body temperature and reduce injury risk.