Question 1: Define a displacement reaction in terms of metal reactivity.

Answer: A displacement reaction occurs when a more reactive metal displaces a less reactive metal from its compound.

Question 2: Explain why aluminium does not readily undergo displacement reactions with dilute acids.

Answer: Because aluminium forms a protective oxide layer that prevents it from reacting easily with acids.

Question 1: List three metals that are more reactive than zinc.

Answer: Potassium, Sodium, Magnesium

Question 2: Describe the general mechanism of a displacement reaction between a metal and a metal salt solution.

Answer: A more reactive metal displaces a less reactive metal from its compound, releasing the less reactive metal as a solid or into solution, often evidenced by a colour change or deposition.

Question 1: Calculate the volume of zinc needed to displace 25 cm³ of copper in a reaction, given the molar ratio is 1:1. Use the molar volume of 22.4 L/mol for gases and assume 1 mol of metal displaces 1 mol of metal salt.

Answer: Zinc volume = 25 cm³ (copper displaced volume) assuming equal molar amounts, so approximately 25 cm³ of zinc is required.

Question 1: Outline a safety procedure to follow when carrying out a displacement reaction involving reactive metals like sodium or potassium.

Answer: Wear appropriate protective equipment, handle reactive metals with tongs, work in a well-ventilated area, and keep reactive metals away from water and moisture.

Question 2: Identify the key variables to control in an experiment to compare reactivity of different metals using displacement reactions.

Answer: Type of metal used, concentration of salt solution, temperature, and contact time.

Question 1: In an experiment, a strip of magnesium reacted with copper sulphate solution, producing bubbles and a colour change. Describe what these observations indicate about the reaction.

Answer: The observations indicate that magnesium displaces copper from its salt, producing magnesium sulphate and copper metal, and that a reaction is occurring.

Question 1: Explain how displacement reactions are used in the electroplating industry.

Answer: Displacement reactions are used to deposit a metal layer onto an object by reducing metal ions from a solution, often involving more reactive metals displacing less reactive metal ions in electrochemical processes.

Question 2: Discuss the environmental implications of using displacement reactions in metal extraction, considering resource sustainability and pollution.

Answer: Displacement reactions can reduce the need for energy-intensive extraction methods like smelting, but improper disposal of metal salts can lead to environmental pollution. Sustainable practices involve recycling metals and minimizing waste.