The interatomic linkage formed by the sharing of an electron pair among two atoms is known as a covalent bond.The binding is caused by the electrostatic attraction of their nuclei for the same electrons. Covalent bonds play an important role in the formation of carbon-based organic molecules such as DNA and proteins. Covalent bonds can also be found in smaller inorganic molecules like H2O, CO2 and O2. A covalent bond is formed when the total energy of the bonded atoms are lower than that of the atoms separated.

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The shared electrons are likely shared equally between both the atoms only when two atoms of the same element form a covalent bond. When atoms of different elements share electrons via covalent bonding, the electron is closely bound to the atom with the higher electronegativity, likely to result in a polar covalent bond. When atoms share their electrons equally, a Nonpolar Covalent Bond is formed. This usually happens when two atoms have similar or identical electron affinities.

What is a Nonpolar Covalent bond?

• A covalent bond is formed by shared pairs of electrons between atoms.
• In a nonpolar covalent bond the atoms which are paired covalently share an equal number of electrons or it can be defined as sharing of electrons where electrons are evenly distributed. Elements with similar electronegativity form nonpolar covalent bonds. 
• There is no net electric charge on these types of molecules as electrical charges cancel each other out.
• The chlorine bond is an example of a nonpolar bond. Chlorine is made up of two chlorine atoms. Since the electronegativity difference between these two atoms is zero, the electrons are shared equally.

Non-covalent bonds are divided into various types, including electrostatic interactions, π-effects, van der Waals forces, and hydrogen bonds. 

1. Electrostatic interactions: are caused by the attraction of groups with opposing electrical charges.
2. Van der Waals forces: are the weak bonds that exist in all molecules. These bonds are caused by dipole-dipole bonds.
3. Hydrogen Bonds: involves the poor sharing of an electron pair among two hydrogen atoms

Importance of Non Polar Covalent Bond in Biology 

• Non-polar covalent bonds are generally strong because they are formed by equal sharing and a high energy is needed to break the bond present between nonpolar covalent bonds.
• In biology, nonpolar covalent bonds seem to be crucially significant. They contribute to the formation of oxygen and assist in the formation of living cells.
• One more application of these types of bonds is that these are contributing to the biological importance in two ways, one by satisfying the need of oxygen for the living organisms and the second one is that it forms peptide bonds in the human body.
• It also contributes to peptide bonding, peptide bonds are the bonds present in long-chain amino acids and these amino acids are further responsible for the contribution of proteins. Proteins are the constituents of a living organism. A living being needs proteins which are one of the macromolecules required for growth and development.
• Non-covalent bonds have a major effect on a liquid’s boiling point. Like one would expect, the stronger a substance’s non-covalent interactions, the greater its boiling point.

What are Nonpolar molecules?

Molecules that have nonpolar covalent bonds are called nonpolar molecules. A nonpolar molecule has no positive or negative poles. Any charges are spread evenly all across the molecule. Nonpolar molecules are generally symmetrical, such as the tetrahedral molecule carbon tetrachloride. One other instance is boron trifluoride, which is trigonal planar. Dipole charges nullify out in symmetrical molecules.

Properties of non-polar polar covalent compound

1. Physical state -These normally occur as gases and sometimes as liquid to a smaller extent.
2. Nature – they are not generally hard as they are elastic in nature or basically soft.
3. Dipole moment-These are nonpolar molecules, they have no polarity and thus have a zero dipole moment .
4. Conductivity-These do not consist of charged particles and do not have the property of conductivity. These compounds act as insulators. 
5. Solubility-These are either water insoluble or have a low water solubility. However, these are more miscible in non-polar solvents such as CCl4, CHCl3, and so on.

Conclusion

The interatomic linkage formed by the sharing of an electron pair among two atoms is known as a covalent bond. A covalent bond is formed by shared pairs of electrons between atoms. A covalent bond is formed when the total energy of the bonded atoms are lower than that of the atoms separated. When atoms of different elements share their electrons, a Nonpolar Covalent Bond is formed. Nonpolar Covalent Bond contributes to the peptide bonding, peptide bonds are the bonds present in long chain amino acids and these amino acids are further responsible for the contribution of proteins. Non-covalent bonds have a major effect on a liquid’s boiling point.