Question

What type of atoms tend to form covalent bonds?

Answer 1

Hint: Covalent bond is a chemical bond formed by equal sharing of electrons between two atoms. Generally, less electropositive elements in the periodic table tend to form a covalent bond with each other by each sharing at least one unpaired electron.

Complete answer:
When two atoms, whether identical or different, equally share their valence electrons in order to gain stability by completing their octet, a bond is formed. Such a type of bond formed by equal sharing of electrons between atoms is known as a covalent bond.
This sharing of electrons in a covalent bond can be visualized by drawing the Lewis dot structures of molecules. For example, the bond between chlorine atoms is covalent.

Usually, the non-metals or atoms having electronegativity difference less than 2.0 Pauling units tend to form a covalent bond. The two non-metals readily form covalent bonds with each other and are capable of forming one to three bonds depending upon the number of electrons taking part in bond formation.
The electron pairs that take part in forming covalent bonds are known as bond pairs and remaining valence electron pairs are known as lone pairs of electrons.
When a metal forms bonds with a non-metal, they are likely to completely transfer electrons to each other while bonding due to the high electronegative difference between the two. This type of bond is known as an ionic bond. For example, NaCl has an ionic bond.
Hence, the covalent bond is formed between two nonmetals.

Note:
The electrons are not always equally shared in a covalent bond. When atoms of different elements share electrons through covalent bonding, the electron transfers partially toward the atom with high electronegativity and as a result, the two atoms acquire partial negative or positive charges.