A Short Note on Polar Covalent Bonds

Various types of chemical bonds are present, polar covalent bond is one of them. When two different atoms of different electronegativity create a bond, that is called a covalent bond, and by sharing an equal number of electrons, this type of bond is known as a Polar Covalent Bond.

Ideally, two completely different atoms of different molecules can only form a polar covalent bond. However, as they have different electronegativity, they will only be able to get the polar covalent bond.

Definition of polar covalent bond

When two different atoms of two different molecules with different electronegativity and different forces of attraction create a bond by sharing electrons to follow octet rule, this bond is known as polar covalent bonds.

Both molecules must be nonmetal to create the compound for a polar covalent bond. Also, the electronegativity of both atoms will be different. And the force of attraction toward electrons as well.

Covalent bond properties

This type of bond has some properties of covalent bonds. Firstly, both of the atoms need to be non-metallic. So, they will tend to share an equal quantity of electrons to follow the octet rule. 

In this bond, not only the tendency but both the atoms share an equal quantity of electrons to create a strong bond.

Polar bond properties

Polar Covalent Bonds have some properties of polar bonds as well. The electronegativity of both atoms is different. This is one of the significant properties of a polar bond.

Along with this, the force of attraction towards the electron of the other atom is also different. So, hold the other atom more strongly to make a bond for this one atom.

Octet Rule

It is really necessary to keep 8 electrons at the last orbit of an atom to make it behave like inert gas. This helps the atom or the atom of any compound to be more stable. This rule is for all the molecules, except for hydrogen and helium. They need 2 electrons at the last orbit to be more stable. This is known as the duet rule.

Properties of polar covalent bonds

This type of bond has some unique properties. As in this bond, both the atoms share an equal number of electrons, and they should share it equally. But one of the atoms will have more electronegativity. Due to the polarity of covalent bonds, that atom will also have more power of attraction towards the sharing electrons. So, that atom will pull the shared electron more towards itself.

If we take hydrochloric acid (HCl), hydrogen will be H+, and chlorine will be Cl–. So, chlorine (Cl–) will have more electronegativity than Hydrogen (H+). With this, Cl– will have more power of attraction towards the shared electrons. So, Chlorine (Cl–) will pull the shared electrons towards it and hold it. This is known as a dipole.

Types Of Substances in Polar Covalent Bond and Its Strength

Polar covalent bonds need both the atoms of molecules to be nonmetal. So if there is one metal, it will not be able to share any electron with another atom. And also, this bond has different electronegativity between two atoms, so those atoms must be of different molecules because atoms from the same molecules will have the same electronegativity.

When it comes to the strength of the bond, this type of bond creates a strong one. But while comparing polar and nonpolar bonds, the nonpolar will have more strength than the polar one. As in the polar covalent bond, the atom with more electronegativity has more power to attract the shared electrons towards it; the other atom will have a chance to break the bond for more stability.

In a polar Covalent Bond, you will be able to find a dipole-dipole attraction like a polar bond, which is why this one is comparably weak.

Conclusion

The Polar Covalent Bond has some properties of both polar bonds and covalent bonds. Both atoms share an equal quantity of electrons to follow the octet rule and get more stability. Due to a polar property, the more electronegative atom can pull the shared electrons towards it.

Due to the properties of the polar bond, this bond creates a dipole, and due to this phenomenon, the strength of the bond is a bit less than the normal or nonpolar covalent bond.