Chemistry 9701/33 March 2017 | Cambridge AS Level Past Papers With Mark Scheme

1. Hydrogen Peroxide Decomposition: Investigating the rate of decomposition of hydrogen peroxide using manganese(IV) oxide as a catalyst, measuring the volume of oxygen produced, and calculating the "volume strength" of the hydrogen peroxide.
2. Titration of Hydrogen Peroxide: Using potassium manganate(VII) to titrate hydrogen peroxide and calculate its molarity, interpreting the stoichiometry and determining the concentration of hydrogen peroxide from titration results.
3. Experimental Improvements: Proposing ways to reduce errors, such as preventing oxygen loss before the bung is inserted, and calculating maximum percentage errors related to equipment accuracy.
4. Qualitative Analysis of Solutions: Identifying cations and anions in various solutions through a series of chemical tests, interpreting the observations such as color changes, precipitate formation, and solubility.
5. Rate and Reaction Mechanisms: Analyzing the effects of concentration changes on reaction rate and drawing conclusions about the relationship between reactant concentration and reaction speed.
6. Chemical Reactions and Error Sources: Discussing the effects of experimental inaccuracies, such as using a less concentrated sodium hydroxide solution, and explaining how these errors impact calculations and identification of acids.