Q1. Define diffusion. [3 marks]

Q2. State the kinetic particle theory assumption that explains diffusion. [2 marks]

Q3. Explain why diffusion occurs faster in gases than in liquids. [2 marks]

Q4. State whether diffusion is a physical or chemical change. Justify your answer. [2 marks]

Q5. Brownian motion provides evidence for the kinetic particle theory. State what Brownian motion is. [2 marks]

Q6. Draw a labelled diagram of the apparatus used to demonstrate the diffusion of ammonia (NH₃) and hydrogen chloride (HCl) gases. [4 marks]

Q7. State the observation when ammonia and hydrogen chloride gases meet. [1 mark]

Q8. Explain why the white ring forms closer to the HCl end of the tube than to the NH₃ end. [3 marks]

Q9. Write the chemical equation for the reaction that produces the white ring. [2 marks]

Q10. Predict what would happen to the position of the white ring if the experiment was repeated at a higher temperature. Explain your answer. [3 marks]

Q11. Explain why the smell of cooking spreads faster on a hot day than on a cold day. [3 marks]

Q12. A drop of food coloring is added to a beaker of water. After 24 hours, the water is uniformly colored. Explain this observation using the kinetic particle theory. [3 marks]

Q13. Two identical balloons are filled with equal volumes of helium (He, Mr = 4) and carbon dioxide (CO₂, Mr = 44). After one week, the helium balloon has deflated more than the carbon dioxide balloon. Explain this observation. [3 marks]

Q14. A student observes smoke particles moving randomly under a microscope. This is called Brownian motion. State what causes the smoke particles to move. [2 marks]

Q15. Bromine gas (Br₂, Mr = 160, red-brown color) diffuses upward into a gas jar of air. Chlorine gas (Cl₂, Mr = 71, pale green color) also diffuses upward into a gas jar. Which gas will diffuse faster? Explain your answer. [3 marks]