Chemistry 9701/32 Oct Nov 2008 | Cambridge AS Level Past Papers With Mark Scheme

1. Determining the concentration of sodium thiosulphate through titration with potassium manganate(VII), using sulfuric acid and potassium iodide solutions, and starch as an indicator.
2. Calculating the moles of potassium manganate(VII) and iodine formed in the reaction and subsequently determining the concentration of sodium thiosulphate using stoichiometric calculations.
3. Estimating the relative molecular mass of a metal carbonate by reacting it with hydrochloric acid and measuring the mass of carbon dioxide evolved.
4. Identifying potential sources of experimental error, such as the dissolution of carbon dioxide in solution, and proposing methods to minimize or eliminate these errors.
5. Testing for cations and anions in solution using sodium hydroxide and ammonia, and applying qualitative analysis methods to identify the substances present in the solutions.