Question

it means graphite conduct electricity whereas diamond doesnt ?

Answer 1

Hello,

You are right with that. Graphite is a good conductor of electricity but diamond is not. Each carbon atom in graphite is directly linked to only three carbon atoms through covalent bonds. Therefore, of the four valence electrons in a carbon atom only three are used for bonding and the fourth is relatively free and can move from one carbon atom to other. This results in the conductivity of graphite.