Chemistry 9701/52 Oct Nov 2022 | Cambridge AS Level Past Papers With Mark Scheme

1. Determining the percentage of calcium carbonate in eggshells through acid dissolution and titration with sodium hydroxide.
2. Investigating the effect of drying and grinding the eggshell, and explaining the purpose of allowing the reaction to occur over two days.
3. Performing calculations based on titration data, including the molar amount of hydrochloric acid and calcium carbonate in the sample.
4. Understanding the method of transferring a specific volume of solution, calculating mass percentage errors, and evaluating the effect of using diluted sodium hydroxide.
5. Discussing the effect of not completely drying the eggshell and potential errors introduced by the use of weaker sodium hydroxide solutions.
6. Analyzing diffusion rates of potassium manganate(VII) and potassium dichromate(VI), including practical issues, safety precautions, and experiment reliability.