Impure copper is purified by electrolysis using an impure copper anode, a pure copper cathode and copper(II) sulfate solution. The only impurities in the anode are zinc and silver.
| Measurement | Mass (g) |
|---|---|
| mass lost by the anode | 15.0 |
| mass gained by the cathode | 14.1 |
| mass of sludge collected below the anode | 0.4 |
Assume that the mass gained by the cathode is equal to the mass of copper lost by the anode.
What mass of zinc dissolved into the solution from the anode?
0.4 g
0.5 g
0.9 g
1.3 g
52 exam-style questions on OCR GCSE Chemistry 3.4 Electrolysis, covering 3.4.1 Products formed at the electrodes in electrolysis and 3.4.2 The technique of electrolysis. Each one has a worked solution and a mark scheme showing where the marks go.