Chemistry 9701/22 May June 2022 | Cambridge AS Level Past Papers With Mark Scheme

1. Explanation of magnesium's high electrical conductivity and melting point based on its structure and bonding.
2. Calculating the oxidation numbers of magnesium and nitrogen in magnesium nitride (Mg3N2) and identifying the type of reaction between magnesium and nitrogen.
3. Definition of enthalpy change of formation and calculation of the enthalpy change for the formation of magnesium nitride.
4. Prediction of the lattice structure of RaCl2 and drawing of the dot-and-cross diagram for RaCl2.
5. Reactions of radium with water, comparison with calcium, and explanation of different reaction rates, including pH observations.
6. Qualitative analysis for halide ions in aqueous calcium halides using step-by-step procedures.
7. Explanation of dynamic equilibrium, writing the equilibrium expression, and calculating the equilibrium amount of HI(g).
8. Calculation of bond energy change for the thermal decomposition of HI(g) and the effect of pressure on Kp.
9. Structural isomerism in the bromination of butane, chiral centers in halothane, and homolytic fission of halothane.
10. Identification of addition polymer structures, challenges in disposal, and suggested improvements for experimental methods.