A chemical cell is used to power a torch. After some time the cell stops producing a potential difference.
Why does this happen?
All of the electrons stored in the cell have been used up.
The metal electrodes have become too hot to react any more.
One or more of the reactants in the cell has been used up.
The wires in the circuit have lost all of their electric charge.
63 exam-style questions on OCR GCSE Chemistry 6.2 Organic chemistry, covering 6.2.1 Crude oil and fractional distillation, 6.2.2 Cracking and dependence on hydrocarbons, 6.2.3 Functional groups and homologous series, 6.2.4 Reactions of alkanes, alkenes and alcohols, 6.2.5 Addition polymerisation and repeat units, 6.2.6 Naturally occurring polymers, 6.2.7 Chemical cells and fuel cells, and 6.2.8 Condensation polymerisation and how to make one. Each one has a worked solution and a mark scheme showing where the marks go.