Organic compounds are substances that contain carbon. There is a vast array of natural and synthetic organic compounds because of the ability of carbon to form four covalent bonds. Carbon can also form giant covalent structures, including diamond and graphite.
The rigid structure, held together by strong covalent bonds, makes diamond very hard. This physical property makes diamond useful for cutting tools, such as diamond-tipped glass cutters and oil rig drills.
Structure and bonding
Graphite has a giant covalent structure in which:
each carbon atom is joined to three other carbon atoms by covalent bonds
the carbon atoms form layers with a hexagonal arrangement of atoms
the layers have weak forces between them
each carbon atom has one non-bonded outer electron, which becomes delocalised
Properties and uses
The delocalised electrons are free to move through the structure, so graphite can conduct electricity. This makes graphite useful for electrodes in batteries and for electrolysis.
The layers in graphite can slide over each other because the forces between them are weak. This makes graphite slippery, so it is useful as a lubricant.