A student set up an electrolysis cell to investigate the electrical conductivity and decomposition products of four different liquids, WWW, XXX, YYY, and ZZZ, at specified temperatures. Their experimental observations are summarized in the table below:
| Liquid | Electrical conductivity | Product at cathode | Product at anode |
|---|---|---|---|
| WWW | Yes | Sodium | Chlorine |
| XXX | No | None | None |
| YYY | No | None | None |
| ZZZ | Yes | Hydrogen | Oxygen |
Which of these liquids are classified as electrolytes under the conditions tested?
WWW and ZZZ only
WWW only
XXX and YYY only
WWW, XXX and ZZZ only
83 exam-style questions on Edexcel GCSE Chemistry 4.2 Electrolytic processes, covering 4.2.1 Electrolytes and the process of electrolysis, 4.2.2 Products of electrolysis using inert electrodes, 4.2.3 Half equations, oxidation and reduction in electrolysis, and 4.2.4 Electrolysis of copper sulfate and purifying copper. Each one has a worked solution and a mark scheme showing where the marks go.