Q. Illustrate Metallic Bonding?
Ans.
A metal is crystalline because it has a regularly repeating, closely packed structure. In a metal, though, this closely packed structure is formed from the positive cations only. These cations are surrounded by mobile valence electrons.
Metal atoms possess loosely held electrons in their outermost, or valence, shell. The electron clouds overlap so that the loosely held valence electrons are free to move between all the metal atoms in the crystal. These valence electrons are said to be delocalized.
A metal crystal consists of a regular packing of positive ions surrounded by delocalized, valence electrons.
Physical properties of metals can be explained by their special type of bonding. For example, metals are malleable and ductile. When a metal is forced into a new shape, the metal atoms settle into new positions.
Often metals are also good conductors of electricity since the electrons in a metal crystal may travel freely.