Giant Covalent Structures

Giant Covalent Structures

1. Quartz

   • Giant macromolecular structures
   • Hard solid
   • High melting and boiling points
   • O between each pair of Si
   • Soluble in water
   • Bent

2. Allotropes of Carbon

   • Graphene
     • Single layers of graphite
     • Covalent network
     • single planar sheet of carbon atoms arranged hexagonally
     • Conducts electricity
     • About 200 times stronger than steel
   • C60 Fullerenes
     • Not completely network solids
     • Small sheet of graphite curved into a ball
     • 60 carbon atoms in the molecule
     • Soluble in non-polar solvents
     • Does not conduct electricity
   • Diamond
     • Three Dimensional Lattice
     • High melting and boiling points
     • Tetrahedral Arrangement
     • Insoluble in covalent solvents
     • Hardest Substance
   • Graphite
     • Naturally Occurring
     • Bonding angle 120º
     • Giant 2-dimensional layers
       • Hexagons of Carbon atoms
       • Each carbon is bonded to three others
       • One free electron layer
     • Trigonal Planar
     • High melting and boiling point
     • Slippery