Chemistry 9701/21 Oct Nov 2020 | Cambridge AS Level Past Papers With Mark Scheme

1. Trends in ionization energies in Group 2 elements, explanations for first and second ionization energy differences, and their correlation with atomic structure.

2. Reactions and properties of phosphorus, sulfur, and chlorine oxides, including hydration, bonding, and atmospheric interactions, and enthalpy calculations for processes involving calcium compounds in SO\\(_2\\) reduction.

3. Structure and bonding in Al\\(_2\\)Cl\\(_6\\), differences between Al\\(_2\\)Cl\\(_6\\) and AlCl\\(_3\\), metallic bonding in LiAlH\\(_4\\) decomposition, and mechanistic steps in reductions with LiAlH\\(_4\\) and NaBH\\(_4\\).

4. Volatility trends and thermal stability of halogens and hydrogen halides, intermolecular force comparisons (e.g., HI vs. HF), and equations for reactions of iodine and alkali hydroxides.

5. Reactions involving iodoalkanes, including mechanisms of CH\\(_3\\)I synthesis, ethene iodination, and elimination reactions to form alkenes; further oxidation and iodine reactions with organic molecules.

6. Mechanistic analysis of propanal cyanohydrin formation, IR spectral interpretation for compound identification, and synthetic pathways for 2-hydroxybutanoic acid.

7. Detailed analysis of halogenated products, including elimination and substitution mechanisms, and product identification from oxidative reactions with alkene intermediates.

8. Observations in halogen reactions with alkalis, color changes, and molecular transformation processes from intermediate stages to final organic compounds.