Structure and bonding in metals

Metallic bonding

Metals consist of giant structures of atoms arranged in a regular pattern.

The electrons from the outer shells of the metal atoms are delocalised, and are free to move through the whole structure. This sharing of delocalised electrons results in strong metallic bonding.

A model showing how metallic bonds are formed. The diagram on top shows the outer electrons in their atoms. The diagram beneath shows that the electrons have become delocalisedA model showing how metallic bonds are formed - the first diagram shows the outer electrons in their atoms, and the second diagram shows that the electrons have become delocalised

Properties of metals

The structure and bonding of metals explains their properties:

  • they are electrical conductors because their delocalised electrons carry electrical charge through the metal
  • they are good conductors of thermal energy because their delocalised electrons transfer energy
  • they have high melting points and boiling points, because the metallic bonding in the giant structure of a metal is very strong - large amounts of energy are needed to overcome the metallic bonds in melting and boiling
Question

Explain why metals can conduct electricity.

Metals conduct electricity because they have delocalised electrons. These carry electrical charge through the metal.