Chemistry 9701/51 May June 2013 | Cambridge AS Level Past Papers With Mark Scheme

1. Solubility behavior of chlorine gas in water with temperature changes, explained using Le Chatelier’s Principle and equilibrium thermodynamics.
2. Experimental plan to determine the concentration of saturated chlorine solution by iodometric titration, involving apparatus, indicator selection, calculations for chlorine and thiosulfate concentrations, and procedural steps for accurate endpoint determination.
3. Hazard analysis and safety measures for handling chlorine and iodine solutions during titration experiments, with specific precautions to mitigate risks of inhalation and contact.
4. Experimental determination of the water of crystallization in hydrated iron(II) sulfate, including molar calculations, mass loss measurement, and graphing moles of water against moles of anhydrous salt.
5. Identification and explanation of anomalous data points in the crystallization experiment, emphasizing potential errors in measurement and heating.
6. Calculation of the slope from experimental data to deduce the formula of hydrated iron(II) sulfate and evaluation of experimental reliability, supported by quantitative analysis of results.