Chemistry 9701/51 May June 2014 | Cambridge AS Level Past Papers With Mark Scheme

1. Thermal decomposition of magnesium nitrate, stoichiometric calculations for MgO, NO₂, and O₂, experimental design for gas absorption and collection.
2. Precautions for handling toxic gases like NO₂, apparatus setup for separate gas collection, measurements of mass, temperature, and volume for quantitative analysis.
3. Electrochemical cell setup using metal M and Ag/Ag⁺ half-cell, dilution effects on Mn⁺ concentration, relationship between cell potential and ion concentration.
4. Graphical analysis of cell potential versus log[Mn⁺], slope interpretation for determining charge (n), calculation of standard electrode potential for metal M.
5. Suitability of salts in salt bridges (KCl, KNO₃, K₂SO₄), explanation of ion mobility and compatibility to prevent side reactions, overall cell reaction.