A technician passes a direct electric current through magnesium bromide solution using inert graphite electrodes.
The ions in the solution are shown in the table.
| Positive ions | Negative ions |
|---|---|
| Mg2+\mathrm{Mg^{2+}}Mg2+ | Br−\mathrm{Br^-}Br− |
| H+\mathrm{H^+}H+ | OH−\mathrm{OH^-}OH− |
The technician predicts that magnesium will form at the cathode and oxygen will form at the anode.
Give the product that actually forms at each electrode.
Explain why the technician's predictions are wrong.
98 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.