Q. Structure of Covalent Bonds?

Ans.

A covalent bond forms between elements that are near each other in the periodic table

While an ionic bond involves an exchange of electrons, a covalent bond involves an overlapping, or sharing, of electrons between the atoms. The overlapping of electron clouds in a hydrogen molecule is shown in the diagram below:

Electron cloud diagrams are rather difficult to draw. A simpler way to show covalent bonding is to sketch electron dot diagrams, using the octet rule.