How is metallic bonding related to alloy formation?

Metallic bonding is related to alloy formation as it allows atoms of different metals to share and delocalise electrons.

Metallic bonding is a type of chemical bonding that arises from the electrostatic attractive force between conduction electrons and positively charged metal ions. It is the main type of bonding that occurs in metallic substances, including alloys. Alloys are mixtures of two or more elements, where at least one element is a metal. The formation of alloys involves the combination of different metal atoms, which is facilitated by the nature of metallic bonding.

In metallic bonding, the electrons are delocalised, meaning they are free to move and are not associated with any particular atom. This delocalisation of electrons results in a 'sea' of electrons that surrounds the metal ions. This electron sea model is what gives metals their unique properties such as high electrical conductivity, malleability, and ductility.

When an alloy is formed, the metal atoms of the different elements come together and their electrons become part of this 'sea'. The different sizes of the atoms can distort the regular arrangement of atoms in the pure metal, leading to a different set of properties. For example, steel is an alloy of iron and carbon where the small carbon atoms fit into the gaps between the larger iron atoms, making the steel harder and stronger than pure iron.

The ability of the metal atoms to share and delocalise electrons in this way is crucial to the formation of alloys. The metallic bonding allows the atoms of the different metals to effectively 'mix' and share their electrons, creating a new substance with different properties. This is why metallic bonding is so important in the formation of alloys.

In summary, metallic bonding, with its characteristic delocalised electrons, allows for the combination of different metal atoms in the formation of alloys. The different atomic sizes involved in alloy formation can lead to a distortion of the regular atomic arrangement, resulting in a change in properties.