Chemistry 9701/52 May June 2013 | Cambridge AS Level Past Papers With Mark Scheme

1. Analysis of calcium hydroxide solubility; prediction of solubility changes with temperature increase based on Le Chatelier’s Principle and enthalpy data, including graphical representation.

2. Planning titration experiments to determine calcium hydroxide concentration; balanced reaction equations, apparatus selection, indicator choice, dilution and titration methods, and calculation protocols for determining solubility in mol dm⁻³.

3. Hazard assessment for titration with Ca(OH)₂ and HCl; identifying risks such as corrosivity and irritant properties, and implementing precautions like protective equipment and controlled reagent handling.

4. Hydrated copper(II) sulfate decomposition experiment; calculation of moles of CuSO₄ and H₂O, plotting a graph to determine the relationship between these quantities, and analysis of anomalous data points with error explanations.

5. Determination of the formula for hydrated CuSO₄ using slope analysis from experimental graph data; correlation between slope and water of crystallization (x) value in CuSO₄·xH₂O.

6. Evaluation of experimental reliability and procedural accuracy in determining hydrate formulas, including the impact of experimental errors and suggestions for improving data reliability.