"Two different forms of carbon – diamond and graphite have different structures and very different physical properties even though their chemical properties are same." Explain why.
Generated by claude-sonnet-4-6 · 2026-06-15 06:51 · grounding rag
Model Answer
Diamond and graphite are both allotropes of carbon, so their chemical properties are the same. However, their physical properties differ due to different structural arrangements:
- Diamond: Each carbon atom is bonded to four other carbon atoms in a rigid, three-dimensional tetrahedral network. This makes it the hardest natural substance and a poor conductor of electricity.
- Graphite: Each carbon atom is bonded to three carbon atoms in flat hexagonal layers. The layers are held by weak forces and can slide over each other, making graphite soft and slippery. One free electron per carbon atom makes it a good conductor.
Since chemical properties depend on the element (carbon) and not its arrangement, both have identical chemical properties.
Source: Chapter 4, Versatile Nature of Carbon (Allotropes of Carbon)
---
Explanation
- The key concept is allotropy — same element, different structural forms.
- Examiners expect you to contrast the bonding in both forms (4 bonds in diamond vs. 3 bonds + free electron in graphite).
- Linking structure → property earns full marks (e.g., rigid network → hardness; layered structure → softness/conductivity).
- The source passages cover covalent bonding and tetravalency of carbon; knowledge of allotrope structures is from the same chapter.