Final answer:
Metal and graphene have different crystal structures. Metals crystallize in closely packed arrays without molecules or covalent bonds. Graphene, however, is a single sheet one atom thick of graphite, composed of a repeated and connected hexagonal structure of carbon atoms.
Step-by-step explanation:
Metal and graphene have different crystal structures. Metals crystallize in closely packed arrays without molecules or covalent bonds. On the other hand, graphene is a single sheet one atom thick of graphite, composed of a repeated and connected hexagonal structure of carbon atoms. This difference in structure gives graphene its unique properties, such as strength, lightweight, and excellent conductivity of electricity and heat.