Metallic Bonding

Metallic bonding, unlike in ionic bonding, involves just one element by itself. By definition (GCSE style) "metallic bonding is the electrostatic attraction between positive metal ions and delocalised electrons". To become a more stable solid, the electrons from the outer shells of the metal atoms delocalise (leave the outer shells) and become free to move about. The electrons spread evenly around the metal ions in order to create a stable metal.

Structurally, the metal ions are arranged into fixed layers which are able to slide across each other, this arrangement is called a metallic lattice. The metal is soft and malleable because the metal layer can slide across each other making it easy to change its shape. For example, when hitting a pure metal with a hammer, it will leave a dent as the layers will slide across each other away from the area of being hit!

Metal alloy (Etienne Martin)

In contrast to pure metals, alloys have a very different reaction to being hit with a hammer. By definition, "an alloy is a mixture of a metal with another element" often other metals. As they are mixtures, the ions and atoms aren't arranged in fixed layers or patterns because they are different sizes. This means that alloys are harder and stronger because they are more resistant to damage and do not change shape easily.

Properties of metals (metallic bonding) include:

• They have high melting and boiling points due to strong electrostatic forces of attraction between metal cations and a delocalized sea of electrons
• Malleable (layer sliding over each other)
• Conducts electricity and heat because delocalized sea of electrons can carry current/heat