Explain how electricity is conducted in a metal.

Metals have a giant metallic structure, with regular closely packed layers of positive ions in a 'sea' of delocalised electrons. What this means is that metals have a large number of positive ions, in a regular arrangements, with delocalised, or free, electrons surrounding them. When an electrical current is passed through the metal, these free electrons are able to move around, and form a current in the metal, passing it on to the next material.