question9

The unbalanced equations for two redox reactions, in which SO2 is involved, are shown below. 9.1 Explain what is meant by the term redox reaction. (2) 9.2 Write down the oxidation number of Mn in: 9.2.1 KMnO4 (1) 9.2.2 MnSO4 (1) 9.3 Is Mn in Reaction 2 OXIDISED or REDUCED? Give a reason for the … Read more

A coil with 200 windings and a surface area of 2,8 × 10-3 m is rotated at constant speed   in a constant magnetic field of 2,5 T. An emf of 3,5 V is induced in the coil. 9.1 Consider the following statement: The magnitude of the induced emf across  the ends of a conductor is … Read more

Learners perform an experiment to determine the emf (ε) and the internal resistance (r)of a battery using the circuit below. 9.1 Which variable has to be kept constant in the experiment? (1) 9.2 Refer to the graph. 9.2.1 Write down the value of the internal resistance of the cell. (2) 9.2.2 Calculate the emf of … Read more

QUESTION 9 (Start on a new page.) Chlorine is produced industrially by the electrolysis of a concentrated sodium chloridesolution, NaCℓ(aq). The balanced equation for the net (overall) cell reaction is as follows: 9.1 Define the term electrolysis. (2) 9.2 For the above reaction, write down the: 9.2.1 Half-reaction that takes place at the cathode (2) … Read more

9.1 A simplified diagram of an electric generator is shown below. When the coil is  rotated with a constant speed, an emf is induced in the coil. 9.1.1 Is this an AC generator or a DC generator?        (1) 9.1.2 Briefly explain how an emf is generated in the coil when the coil is rotated by referring … Read more