Metallic bonding is the bonding within metals. It involves the delocalized sharing of free electrons between a lattice of metal atoms. Thus, metallic bonds may be compared to molten salts.
e.g. Iron (Fe)... Why is it so strong? Of course, metallic bonding.
Metal atoms typically contain a small amount of electrons in their valence shell compared to their period or energy level. These become delocalised and form a Sea of Electrons surrounding a giant lattice of positive ions.
Metals seem to have higher boiling and melting points which might suggest stronger bonds between the atoms.
Metallic bonding, as with covalent bonding is non-polar, in that there is no (for pure elemental metals) or very little (for alloys) electronegativity difference among the atoms participating in the bonding interaction, and the electrons involved in that interaction are delocalized across the crystalline structure of the metal.
The metallic bond accounts for many physical characteristics of metals, such as strength, malleability, ductility, conduction of heat and electricity, and luster. See also chemical bond.
Metallic bonding is the electrostatic attraction between the metal atoms or ions and the delocalised electrons. This is why atoms or layers are allowed to slide past each other, resulting in the characteristic properties of malleability and ductility.
Metallic bond are different from chemical bonds. Ionic and covalent bonds are chemical bonds.
Covalent bonding is a common type of bonding, in which the electronegativity difference between the bonded atoms is small or non-existent. In the latter case, the bond is sometimes referred as purely covalent. See sigma bonds and pi bonds for current LCAO-explanation of non-polar bonds.
e.g. CH4 (methane)
Ionic bonding is type of electrostatic bond between atoms which have an electronegativity difference of over 1.6 (this limit is a convention). These form in a solution between two ions after the excess of the solvent is removed.
e.g. NaCl (common salt)
Hey, I tried to draw the structures of NaCl and methane molecules but this Yahoo! made it impossible. I hope you know the structurel.