Chemistry 9701/52 Oct Nov 2019 | Cambridge AS Level Past Papers With Mark Scheme

1. Reflux and distillation setup: Apparatus construction and operational procedures for controlling exothermic reactions, cooling water flow, and handling reactions under reflux.
2. Separation and purification techniques: Use of distillation for separating liquid components, followed by crystallization to isolate pure products from mixtures.
3. Enthalpy change and calorimetry: Calculation of the enthalpy change of fusion of naphthalene, plotting data for mole fraction and melting point, and interpretation of experimental results to estimate enthalpy values.
4. Error analysis and reliability: Impact of incorrect molecular weight on calculations, analysis of experimental procedure reliability, and comparison of theoretical and experimental enthalpy values.
5. Reaction mechanisms and product identification: Identifying halogenoalkanes in organic reactions, effects of using different halogenoalkanes in organic synthesis, and understanding reaction mechanisms like nucleophilic substitution.
6. Thermodynamics and mixing effects: Understanding endothermic and exothermic mixing and their effects on enthalpy changes during phase transitions.