Question

Using electron-dot diagrams which show only the outermost shell electrons, show how a molecule of oxygen, O₂, is formed from two oxygen atoms. What name is given to this type of bonding?

(At. No. of oxygen = 8)

Answer 1

Oxygen has an atomic number of 8, resulting in an electronic configuration of 2, 6. Thus, an oxygen atom possesses 6 electrons in its valence shell. Since an oxygen atom has 6 electrons in its outermost shell, it requires 2 more electrons to achieve the stable, 8-electron inert gas configuration. The oxygen atom acquires these electrons by sharing its two electrons with the two electrons of another oxygen atom. Two oxygen atoms each share two electrons, forming a stable oxygen molecule.

The bond between the oxygen atoms, characterised by the sharing of two pairs of electrons, is called a double covalent bond, or simply a double bond. Therefore, in the oxygen molecule, the two oxygen atoms are linked by a double bond.