A technician tests a material being considered for a high-temperature electrical contact.
The technician records these observations.
| Property | Observation |
|---|---|
| Melting point | 1455 ∘C1455\,^\circ\mathrm{C}1455∘C |
| Conducts electricity when solid? | Yes |
| Effect of being pressed | Changes shape without cracking |
What type of particle arrangement accounts for all three observations?
Long covalent chains held together by weaker forces
Alternating positive and negative ions fixed in a lattice
Layers of positive ions attracted to delocalised electrons
Hollow cage molecules held together by intermolecular forces
122 exam-style questions on OCR GCSE Chemistry 2.3 Properties of materials, covering 2.3.1 Carbon bonding and the variety of organic compounds, 2.3.2 Diamond, graphite, fullerenes and graphene, 2.3.3 Bond strength, changes of state and predicting states, 2.3.4 Bulk properties and types of bonding, and 2.3.5 Nanoparticles: scale, surface area, uses and risks. Each one has a worked solution and a mark scheme showing where the marks go.