Difference between diamond and graphite.
| Diamond | Graphite |
| 1. It is the hardest substance known to exist. | 1. It is black greyish crystalline solid and is quite soft. |
| 2. It is a bad conductor of electricity. | 2. It is a good conductor of electricity. |
| 3. The carbon atoms in the structure are sp3 hybridised. | 3. The carbon atoms are sp2 hybridised. |
| 4. It has huge three dimensional network structure. | 4. It has two dimensional sheet like structure. |
| 5. It does not possess any lustre | 5. It a has metallic lustre. |
| 6. It a has very high melting point. | 6. It has low metling point. |
What are allotropes? Sketch the structure of two allotropes of carbon family namely diamond and graphite. What is the impact of structure on physical properties of two allotropes?
