Question

Though both diamond and graphite are purest forms of carbon only graphite can conduct electricity. Explain.

Answer 1

Hint: We know that carbon has an atomic number of six. The electronic configuration of the carbon atom can be written as $1{s^2},2{s^2}2{p^2}$. We can observe that it has four valence electrons. Diamond and graphite are purest forms of carbon. Graphite is a good conductor of electricity and diamond is a bad conductor of electricity.

Complete step by step answer:
As we know that the graphite has a layered structure. It has a giant structure. The carbon atoms of graphite form a hexagonal structure, arranged in a layered way. The carbon atoms of the graphite have delocalised electrons. Each carbon atom is bonded with three other carbon atoms. One valence electron is not bonded, which helps in conducting electricity.
On the other hand, diamond is a giant covalent structure. Each carbon atom of diamond is connected with four other carbons. It does not have any unpaired electrons. All four valence electrons of the carbon atom are bonded with different carbon atoms. Because of this reason diamonds cannot conduct electricity.
So, from the above explanation and discussion it is clear to us that graphite has free electrons due to which it can conduct electricity and diamond doesn't have any free electrons due to which it cannot conduct electricity.

Additional information:
Diamond is the hardest substance on earth due to its structure. It has a very low coefficient of friction, it also has high thermal conductivity. Diamond has face centred cubic structure. When graphite is applied high pressure and temperature it gets converted into diamond.

Note:
Always remember that every carbon atom of the graphite is connected to three other carbon atoms, that means every carbon of graphite has a free electron which helps in conducting electricity. Every carbon atom of the diamond is connected to four other carbons, there are no free electrons so it cannot conduct electricity. The electronic configuration of carbon is $1{s^2},2{s^2}2{p^2}$.