Question

how will you explain that diamond is non conductor while graphide is conductor in nature ?​

Answer 1

Diamond has 3D carbon network so the structure is rigid with carbon bonded to four other carbon in space.
This is the reason that diamond is hardest substance known. Since all the four carbon atoms are involved in bonding and there is no free electron in the crystal structure of diamond. Therefore diamond is non-conductor of electricity.
Graphite has two dimensional sheet like structure. Each carbon atom is covalently bonded to three other carbon atom and fourth electron is forms a π bond. The various layers are held together by weak van der Waals forces of atoms. This is the reason graphite has soft and slippery structure. The electrons are delocalised over the whole sheet and they are mobile. Therefore diamond is a good conductor of electricity.

Answer 2

Explanation:

ᎽᎾuᏒ ᎪᏁsᎳᎬᏒ

In a graphite molecule, one valence electron of each carbon atom remains free, Thus making graphite a good conductor of electricity. Whereas in diamond, they have no free mobile electron. Hence there won't be flow of electrons That is the reason behind diamond are bad conductor electricity