1.14 Diamond & graphite

Name two giant covalent structures formed from carbon atoms

Graphite Diamond

Describe the structure and properties relating to graphite

Each carbon atom bonded to 3 other carbon atoms. Layers of hexagonal rings of carbon atoms. Weak intermolecular forces between layers. One delocalised electron per carbon atom.

Describe and explain the properties of graphite

Graphite is soft / slippery because there are only weak intermolecular forces between layers which allow the layers to slide over one another. Graphite conducts electricity because there is one delocalised electron per carbon atom. The delocalised electrons are mobile charges.

Describe the structure of diamond

All carbon atom are covalently bonded to four other carbon atoms. No delocalised electrons.

Describe the properties of diamond

Very hard. Very high melting point. Doesn’t conduct electricity as there are no charged particles.

What are the uses of graphite? Why?

Electrodes because graphite conducts electricity and has a high melting point. Lubricant because it’s slippery (the layers in graphite can slide over each other).

Why is diamond used in cutting tools?

It’s very hard.