Giant covalent structures

• Properties of graphite:

  Conducts electricity

  Opaque

  Soft and easily separated into layers due to weak Van der Waal's forces between layers (lubricant)

  Very high sublimation point- 3730°C
• Graphite is used as an electrical conductor, lubricant, and electrode material.
• Structure and Bonding of graphite:
• Structure and Bonding of graphite:

  Each carbon atom is covalently bonded to 3 other carbon atoms, leaving the fourth 2p electron free to move between layers

  It consists of weak Van der waal's forces between sheets/layers

  Each sheet/layer is a macromolecule

  The arrangement of carbon atoms is hexagonal with a bond angle of 120°
• Properties of Diamond:

  Insulator

  Transparent

  Hardest naturally occurring material

  3D network

  High melting point

  Hard
• Uses of diamond:

  drill tips

  cutting tools
• Structure and Bonding of diamond:

  It is a macromolecule

  Each carbon atom is covalently bonded to 4 carbon atoms

  The arrangement around each carbon atom is tetrahedral

  The bond angle is 109.5°

  There are no spare electrons so the molecule is neutral