Answer to Question #226247 in Molecular Physics | Thermodynamics for Fazi

Question

b). Explain the occurrence of metallic bonding with at least two examples

Answer 1

Metallic bonding is a type of chemical bonding that arises from the electrostatic attractive force between conduction electrons (in the form of an electron cloud of delocalized electrons) and positively charged metal ions.

Examples:

1. Sodium (Na)

Sodium has a lone electron in its outermost orbital, i.e., the 3s orbital. When sodium atoms arrange together, the outermost electron of one atom shares space with the corresponding electron on a neighboring atom. As a result, a 3s molecular orbital is formed. Each sodium atom has eight other atoms in its neighbor. The sharing takes place between a central sodium atom and the 3s orbital of its neighbors.

All the 3s orbitals overlap to give many molecular orbitals that extend over the entire sodium metal. The outermost electrons are said to be delocalized over the whole metal structure. These electrons are no longer attached to any particular atom but move freely around the entire metal.

2. Magnesium (Mg)

Magnesium has two electrons in its outermost shell, the 3s shell. Both these electrons are delocalized. The metallic bond formation in magnesium is the same as sodium, except it has more electron density than sodium. Besides, each of magnesium nucleus has a twice the charge as in sodium. Therefore, the attraction between the nuclei and the delocalized electrons will be stronger than sodium. The strength of the bond is generally higher in magnesium.