Scientists used a computer model to compare ordinary graphite, sample G, with sample M. Sample M is a hypothetical modified form of graphite with the same layered arrangement. Only the forces between its layers have been altered.
| Sample and change | Modelled energy required in kJ/mol |
|---|---|
| G: move one layer over a neighbouring layer | 5 |
| G: break covalent bonds within a layer | 350 |
| M: move one layer over a neighbouring layer | 40 |
Use the data to explain why sample G is soft but has a very high melting point. Suggest whether sample M would be more or less soft than sample G. Justify your answer.
68 exam-style questions on AQA GCSE Chemistry 2.3 Structure and bonding of carbon, covering 2.3.1 Diamond, 2.3.2 Graphite, and 2.3.3 Graphene and fullerenes. Each one has a worked solution and a mark scheme showing where the marks go.