Structure and Bonding of Carbon

Structure and Bonding of Carbon

Structure of Carbon Atom

  • An atom of carbon contains 6 protons and typically 6 neutrons in its nucleus.
  • Carbon has 6 electrons, two in the inner shell and four in the outer shell, represented as 2,4 in electron configuration.
  • The four outer shell or valence electrons can form covalent bonds with other atoms.

Bonding in Carbon

  • Carbon can form either single, double, or triple covalent bonds with other carbon atoms or atoms of different elements.
  • In forming covalent bonds, carbon atom shares its valence electrons with other atoms.

Carbon Allotropes: Diamond

  • Diamond is a form of carbon with each atom covalently bonded to four other carbon atoms in a tetrahedral arrangement.
  • This makes diamond a giant covalent structure, resulting in its incredibly high melting point and hardness.
  • Diamond is non-conductive as it does not possess free electrons or ions to carry an electric charge.

Carbon Allotropes: Graphite

  • Each carbon atom in graphite is covalently bonded to three others, forming layers of hexagonal rings.
  • The fourth electron in each carbon atom is delocalised, creating a ‘sea of electrons’.
  • These delocalised electrons allow graphite to conduct electricity, unlike diamond.
  • The layers in graphite are held together by weak van der Waals forces, making them able to slide over each other and giving graphite its slippery nature.

Fullerenes and Nanotubes

  • Fullerenes, including buckminsterfullerene (C60), are molecules of carbon atoms with hollow shapes.
  • They can form intermolecular ‘cages’ to enclose or transport other atoms or molecules.
  • Carbon nanotubes, a type of fullerene, have a cylindrical shape and are known for their remarkable strength and electrical conductivity.
  • Both fullerenes and carbon nanotubes are examples of nanotechnology in chemistry.

Key Understanding Points

  • Know the atomic structure of carbon.
  • Understand the types of covalent bonding involved in the formation of different carbon structures.
  • Be clear about the properties of carbon structures, including the allotropes diamond and graphite.
  • Understand the applications of fullerenes and carbon nanotubes in the field of nanotechnology.
  • Be able to draw the structures of basic carbon allotropes and describe their properties.