Question 1: Explain what a displacement reaction is in the context of metals and how it can be utilised in nanotechnology.

Answer: A displacement reaction involves a more reactive metal replacing a less reactive metal in a compound. In nanotechnology, this process can be used to synthesise metal nanoparticles by depositing reactive metals onto substrates or existing nanostructures.

Question 2: Which metal is most likely to displace copper from its salt solution in a displacement reaction?

Answer: Zinc

Question 1: Define a displacement reaction and describe its significance in nanotechnology manufacturing.

Answer: A displacement reaction is a chemical process where a more reactive metal displaces a less reactive metal from its compound. In nanotechnology, this allows precise deposition of metals at the nanoscale, enabling the creation of specialised nanostructures.

Question 2: Describe how the reactivity series of metals influences the outcome of displacement reactions used in nanotechnology.

Answer: Metals higher in the reactivity series are more likely to displace metals lower in the series. This helps control which metals are deposited onto nanomaterials, ensuring desired properties in nanotech applications.

Question 1: Calculate the mass of zinc needed to displace 10 g of copper from its salt solution, given the molar masses: Zn = 65.38 g/mol, Cu = 63.55 g/mol. Use the reaction: Zn + CuSO4 → ZnSO4 + Cu.

Answer: The molar ratio of Zn to Cu is 1:1. Moles of Cu = 10 g / 63.55 g/mol ≈ 0.157 mol. Therefore, mass of Zn = 0.157 mol × 65.38 g/mol ≈ 10.27 g.

Question 2: If 5 grams of zinc are used in a displacement reaction, how much copper can theoretically be displaced?

Answer: Number of moles of Zn = 5 g / 65.38 g/mol ≈ 0.0765 mol. Moles of Cu displaced = 0.0765 mol. Mass of Cu displaced = 0.0765 mol × 63.55 g/mol ≈ 4.87 g.

Question 1: Design a basic experiment to observe a displacement reaction between zinc and copper sulfate solution. Outline the variables involved and safety precautions.

Answer: The experiment involves adding zinc metal to a copper sulfate solution and observing the formation of copper metal on zinc. Variables include the concentration of the solution, temperature, and surface area of zinc. Safety precautions include wearing gloves and goggles, working in a well-ventilated area, and disposing of chemicals properly.

Question 1: In an industrial process, a metal surface is treated with a solution containing a less reactive metal ion. After reaction, a layer of a different metal is formed. Explain how displacement reactions facilitate nanostructure formation in this context.

Answer: Displacement reactions enable selective deposition of metals onto surfaces at the nanoscale by replacing less reactive metal ions with more reactive metals. This process allows precise control over nanostructure formation, useful in electronics and catalysis.

Question 1: Explain why zinc can displace copper from its salt solution but gold cannot. Include reference to the reactivity series in your answer. (6 marks)

Answer: Zinc is higher in the reactivity series than copper, meaning it is more reactive and can displace copper from its compounds. Gold is lower in the series, making it less reactive; therefore, it cannot displace copper or other metals below it in reactivity from their salts.