The structures of two allotropes of carbon are represented above. Which of the following statements best helps explain why diamond is much harder than graphite?
answer choices
Diamond contains covalent bonds, whereas graphite contains ionic bonds.
Diamond contains ionic bonds, whereas graphite contains covalent bonds.
Carbon atoms in diamond have four covalent bonds, whereas graphite is made of layers that are held together by relatively weak dispersion forces.
Carbon atoms in diamond have a sea of mobile electrons that make the structure strong, whereas graphite does not contain delocalized electrons.
