Answer:
Carbon atoms each form four strong bonds. The bonds are covalent (atoms share electrons). This gives graphite its characteristic properties such as high melting and boiling points, good electrical conductivity, and softness. Use as pencil 'lead', as a lubricant in oil, furnace linings, electrodes, neutron moderators in nuclear power stations.
Diamond atoms each form three strong covalent bonds in the same layer and one weak bond to an atom in another layer. Diamonds have a high level of hardness, thermal conductivity, and optical dispersion. It is used for jewellery, oil-well drills, abrasives and cutting tools.
Step-by-step explanation:
Structure of Graphite and Diamond (attached below):