will give brainliest if you answer all of them

Answer:
Explanation:
A. Graphite can conduct electricity because of the delocalised (free) electrons in its structure. These arise because each carbon atom is only bonded to 3 other carbon atoms. ... However, in diamond, all 4 outer electrons on each carbon atom are used in covalent bonding, so there are no delocalised electrons.
B. Diamond is hard because the carbon atoms in diamond are bonded in a stronger tetrahedron pattern but graphite is soft and slippery because the carbon atoms in graphite are bonded in layers with only weak vanderwall force holding the layers together.