A student places two graphite electrodes into solid lead bromide in a crucible. The electrodes are connected to a dc power supply and a bulb. The bulb does not light.
Which change would allow electrolysis to happen?
Heat the lead bromide until it melts
Replace the graphite electrodes with copper electrodes
Reverse the connections to the power supply
Add more solid lead bromide to the crucible
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.