Chemistry 9701/23 May June 2019 | Cambridge AS Level Past Papers With Mark Scheme

1. Chlorine and Metal Carbonates: Preparation of chlorine from MnO2 and hydrochloric acid, observation of the reaction, and understanding the trend in volatility within Group 17.
2. Disproportionation Reactions: Identifying disproportionation reactions of chlorine with sodium hydroxide, including products and oxidation states involved.
3. Copper in Brass: Determining the percentage of copper in brass by titration, calculating the concentration of Cu2+ ions, and understanding the relationship between absorbance and concentration.
4. Viscosity Measurements: Using capillary viscometers for poly(phenylethene), analyzing the relationship between viscosity and molecular mass, and predicting the effect of temperature on the measurements.
5. Reaction Mechanisms: Understanding nucleophilic substitution mechanisms for halogenoalkanes, explaining SN1 and SN2 mechanisms, and identifying suitable reagents