Structure + Bonding of Carbon

What are the 5 allotropes of carbon?

Diamond, Graphite, Graphene, Nanotubes and Fullerenes

Describe and explain the properties of diamond.

• Four, strong covalent bonds for each carbon atom

• Very hard

• Very high melting point

• Does not conduct

Why doesn’t diamond conduct electricity?

Diamond has no delocalised electrons or ions that can carry charge through the structure.

Why does diamond have a very high melting point?

Diamond has strong covelent bonds that require a lot of energy to overcome

Why is diamond very hard?

It has strong covalent bonds.

Describe and explain the properties of graphite.

• Three covalent bonds for each carbon atom

• Layers of hexagonal rings

• High melting point

• Layers free to slide as weak intermolecular forces between layers

• Soft

• Conduct thermal and electricity

Why can graphite conduct electricity and heat?

Graphite has one delocalised electron per carbon atom that can carry charge through the structure.

Why does graphite have a high melting point?

It has strong covalent bonds that require a lot of energy to overcome.

What is graphene?

A single layer of graphite.

Describe and explain the properties of nanotubes.

• Cylindrical fullerene with high length to diameter ratio

• High tensile strength

• Conductivity of electricity and heat

Why do nanotubes have high tensile strength?

They have strong covalent bonds.

Why are nanotubes able to conduct heat and electricity?

They have delocalised electrons which can carry charges through the structure.

Describe and explain the properties of fullerenes.

• Hollow shaped molecules

• Based on hexagonal rings but may have 5/7-carbon rings

• C₆₀ has spherical shape, simple molecular structure (Buckminsterfullerene)