Chemistry 9701/23 Oct Nov 2021 | Cambridge AS Level Past Papers With Mark Scheme

1. Sulfur and carbon compounds including CS2's volatility, bond angles, and intermolecular forces affecting physical states, enthalpy changes of combustion, weak acid definitions, redox analysis, and environmental impacts of SO2.

2. Group 2 compounds including thermal stability trends, reaction equations, uses of Ca(OH)2 in agriculture, and synthesis of calcium derivatives like CaC2 and CaCN2, incorporating hybrid orbital theory.

3. Phosphorus allotropes and reactivity, reaction equations for P4 derivatives, and applications in Wittig reactions, including organic synthesis mechanisms and empirical formula calculations.

4. Multi-step organic reaction schemes involving oxidation, esterification, and catalysis with sulfuric acid, infrared spectroscopy analysis for functional group identification, and reaction equations for derivatization.

5. Chemical equilibrium, oxidation states, and hybrid orbital interactions in reactions involving halides, phosphorus oxides, and other molecular systems under different conditions.

6. Environmental and industrial chemistry concepts, including greenhouse gas impacts, pollutant neutralization, and agricultural applications of compounds like Ca(OH)2 and CaCN2, with quantitative and structural analysis of reaction products.