The table below shows that carbon can exist as several different structures called allotropes.
| Allotrope | Covalent bonds per carbon atom |
|---|---|
| Diamond | .............. |
| Buckminsterfullerene (C60C_{60}C60) | .............. |
| Graphite | 3 |
Complete the table to show how many covalent bonds each carbon atom forms in these allotropes.
Graphite is an excellent conductor of electricity, while diamond is an electrical insulator. Explain this difference in conductivity. Use ideas about structure and bonding in your answer.
Buckminsterfullerene (C60C_{60}C60) has a relatively low melting point (280∘C280^\circ\text{C}280∘C), whereas diamond has an extremely high melting point (above 3500∘C3500^\circ\text{C}3500∘C). Explain this difference in melting points. Use ideas about structure and bonding or intermolecular forces in your answer.
Explain why carbon is able to form a vast array of millions of different compounds. Use ideas about the bonding of carbon in your answer.