Metallic bonds are the chemical bonds that hold atoms together in metals. They differ from covalent and ionic bonds because the electrons in metallic bonding are delocalized, that is, they are not shared between only two atoms. Instead, the electrons in metallic bonds float freely through the lattice of metal nuclei. This type of bonding gives metals many unique material properties, including excellent thermal and electrical conductivity, high melting points, and malleability.

Metallic Bond:
These are formed when the valence electrons of metal atoms are shared by more than one neighboring atom. The metal atoms are held together by a “sea” of electrons floating around. Metals consist of a lattice of positive ions through which a cloud of electrons moves. The positive ions will tend to repel one another, but are held together by the negatively charged electron cloud. The mobile electrons, known as conduction electrons, can transfer thermal vibration from one part of the structure to another i.e., metals can conduct heat. They are good conductors of electricity also.

Example:
The metal atoms Na, Cu, Ag, Fe etc., are bound to each other in their crystals by metallic bond.

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