Chemistry 9701/53 Oct Nov 2018 | Cambridge AS Level Past Papers With Mark Scheme

1. Finkelstein Reaction Mechanism: Using dry propanone as a solvent in the nucleophilic substitution reaction, explaining its role in facilitating the reaction between halogenoalkanes and halides like NaI.
2. Solubility and Yield in Finkelstein Reaction: Understanding the high yield of the reaction due to the solubility differences between NaI and NaBr in propanone, leading to an irreversible reaction.
3. Safety Measures in Laboratory: Identifying necessary precautions to prevent inhaling toxic gases or handling highly flammable substances, with explanations for each safety measure.
4. Experimental Setup for Reaction Rate: Investigating how NaI concentration affects the rate of reaction using timed observations and calculating the required volumes of reactants for consistent experiments.
5. Inaccuracies and Improvements in Experiment: Identifying the sources of inaccuracies in reaction time measurement and suggesting improvements to increase accuracy.
6. Temperature and Mechanism Effects: Analyzing the effect of temperature and the reaction mechanism (SN2 vs. SN1) on the rate of reaction in halogenoalkanes with NaI.