Chemistry Level 2

Giant covalent structures and nanomaterials

Giant covalent structures - 1

• Diamond and graphite are forms of carbon with giant covalent structures.

• Fullerenes are another form of carbon used to form nanotubes.

Giant covalent structures - 2

• Thermosoftening polymers do not have cross links between chains.

• They can be melted.• So they can be recycled

Giant covalent structures - 3

• Thermosetting plastics have long chains with cross-links

• This holds the chains in place and makes the plastic rigid – so they can’t be recycled

Nanoparticles

• Fullerenes are examples of nanoparticles

• Nanoparticles are made up of a few hundred atoms

• They measure between one nanometre and 100 nanometres across

Nanoparticles are useful

• Nanotubes have very large surface areas compared with their volumes so make excellent catalysts

• Nanotubes can be used to reinforce tennis rackets because they are so strong and stiff, yet light

• Fullerene cages can deliver dangerous drugs to the site of a tumour or infection

• Nanoparticles are being used for self-cleaning ovens and windows