Chemistry 9701/42 Oct Nov 2013 | Cambridge AS Level Past Papers With Mark Scheme

1. Structural bonding in ammonium chloride, including ionic, covalent, and coordinate bonds, with dot-and-cross diagram representation.
2. Thermal decomposition and stability trends of Group II nitrates, including calcium nitrate, with reaction equations and group analysis.
3. Melting point trends in Group IV elements, explained by bonding and atomic structure variations.
4. Acid-base concepts using Brønsted-Lowry theory, buffer solutions, and pH calculations for weak acids and their conjugate bases.
5. Bond energies in halogenoalkanes, trends in reactivity based on bond strength, and implications for CFCs' impact on ozone depletion.
6. Reaction mechanisms in organic and environmental chemistry, including free radical substitution, electrophoresis setup, and partition coefficient applications.
7. Environmental chemistry covering nitrate and phosphate contamination in water bodies, acid rain formation from sulfur dioxide, and water purification methods using calcium carbonate.