Chemistry 9701/23 May June 2021 | Cambridge AS Level Past Papers With Mark Scheme

1. Trends in van der Waals forces, halogen reactivity, and oxidizing agent strength in Group 17 elements; redox reactions of halides and halogens; sodium chlorate(I) reactions with hydrochloric acid.

2. Hydrogen bonding in methanol and water; vapor pressure dynamics and intermolecular forces; equilibrium and partial pressure calculations for methanol synthesis from carbon monoxide and hydrogen; equilibrium constant expression and units.

3. Identification of chemical compounds through reaction observations with water; characterization of ceramic materials and Period 3 oxides; empirical formula determination for tungsten oxide.

4. Organic reaction mechanisms involving 1,3-dichloropropan-2-ol and 3-chloropropane-1,2-diol; oxidation reactions with Cr₂O₇²⁻; reagent identification and reaction condition analysis for multi-step synthesis of citric acid.

5. Structural and functional analysis of citric acid and a chiral isomer; stereoisomerism criteria; structural isomer identification and comparison of chemical reactivity with sodium and acidified Cr₂O₇²⁻.

6. Integration of thermodynamics, reaction kinetics, and structural chemistry principles in evaluating halogen chemistry, organic synthesis, and equilibrium systems.