Chemistry 9701/53 May June 2018 | Cambridge AS Level Past Papers With Mark Scheme

1. Apparatus Setup for Electrolysis: Drawing a labeled diagram for an electrolysis experiment to determine the Faraday constant, showing the required chemicals and equipment, and connecting the circuit between the anode and cathode.
2. Safety Precautions: Identifying appropriate safety precautions for handling copper(II) sulfate to prevent skin irritation and harm to aquatic life.
3. Measuring Mass Change in Electrolysis: Stating the necessary measurements for calculating the mass change of the electrodes during electrolysis.
4. Charge Calculation: Using the formula for charge (C = current × time) to calculate the charge passed during electrolysis.
5. Copper Loss Calculation: Determining the moles of copper lost from the anode based on the mass change, and calculating the charge required to remove 1 mole of copper.
6. Understanding the Faraday Constant: Explaining why the theoretical charge to remove 1 mole of copper is twice the Faraday constant.
7. Effect of Wet Anode: Explaining the impact of starting with a wet anode on the accuracy of the calculated Faraday constant.
8. Blackening from Flame Exposure: Suggesting the cause of blackening when using a blue Bunsen flame to evaporate propanone.
9. Inconsistency in Mass Change: Providing a reason for discrepancies in the mass lost at the anode and gained at the cathode, assuming correct mass recording.
10. Investigation of Benzenediazonium Ion: Investigating the reaction of C6H5N2+ with water, determining concentration changes, and plotting graphs to analyze the rate of gas production.