Hello friends, you can have countless doubts about the polarity in some molecules in the chemistry world. Numerous of us have a doubt concerning the polarity of SO2 (sulfur dioxide). So, I will certainly share my details with friend to clean the doubt regarding the polarity of SO2.

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Is SO2 polar or nonpolar? SO2 is polar in nature due to the fact that of the difference in electronegativity between sulfur and oxygen atoms. The higher the distinction in electronegativity an ext will it is in the polarity of the molecule. The bent shape of SO2 is because of the repulsion in between the unbonded electrons current on the sulfur and oxygen atoms. The unsymmetrical shape also identifies whether a molecule is polar or not.

Why is SO2 Polar?

In the SO2 molecule, the Sulfur has actually 6 electrons in its vacant shell and Oxygen additionally has 6 electrons in that vacant shell. 4 electrons of sulfur bond v the 2 pairs of electron from both oxygen atoms around sulfur.

And after bonding in the SO2 molecule, the uneven charge stays on Sulfur and also Oxygen. 2 unbonded electrons stay on Sulfur and 4 electron on both that the Oxygen atoms.

Therefore, unlike charge distribution occurs after the bonding of the SO2 molecule. The lone pair current on Sulfur and lone current on Oxygen atoms causes repulsion in between each other.

The Sulfur is an ext electronegative than Oxygen, as a result, the Oxygen-Sulfur bond shares unequal fee distribution, and the bond developed in it is polar.

According to the VSEPR theory, the repulsion in between two lone pairs is higher than the repulsion in between the lone pair and bond pair.

Similarly, in the SO2 case, the lone pair existing on Sulfur and Oxygen atoms produces repulsion between them.

In such situations as SO2, where an ext than one lone pair team is present, the geometrical shape of the molecule is slightly different as compared to the molecule wherein all teams are bonds.

Factors affect the polarity the a chemical compound

The polarity that a molecule is decided based on the uneven charge circulation of the atoms affiliated in the molecule. The uneven charge distribution results in the net dipole moment.

The molecule which has actually a non-zero worth of network dipole moment is polar vice versa, the molecule which has actually net dipole moment equals zero is non-polar. The CO2, O2 is an example of non-polar molecules.

You deserve to read out the article for the factor of the non-polarity that CO2.

The molecules that have actually zero network dipole minute is because of equal charge distribution on the atom in the molecule. Therefore, the dipole minute gets canceled out and results in a net-zero dipole moment.

Dipole moment = Bond length * charge on each element

The calculation dipole moment of SO2 (sulfur dioxide) is 1.6 debyes.

It is far better to know that the distinction in electronegativity is among the main determinants that affect polarity.

The polarity of a molecule is directly proportional come the difference between the electronegativities that the atoms affiliated in the molecule.

The polarity and also non-polarity of a molecule depends on the various factors such as

Molecular geometry the the moleculeThe number of identical atoms present.The variety of lone pairs existing in the molecule.The the contrary of the molecule.

In the world of chemistry, electronegativity is a measure of exactly how strongly an atom can tempt an electron in the direction of itself.

More electronegative atom have the right to strongly attract electron and also low electronegative atom have the right to weakly entice the electron.

SO2 shortcut Angle


The SO2 molecule creates the form of the trigonal planar. The lone pair repulsion among the Oxygen and Sulfur creates a bent shape and the angle in between the bonds is found to be approximately 119-120 degrees.

The place of the atoms in the SO2 is such the the Sulfur atom is current in the center/between both of the Oxygen atoms.

However, the lone pair current on the Sulfur atom reasons repulsion through the lone pair existing on the Oxygen atoms bring about the V-shape/bent-shaped SO2 molecule.

The bond angle in SO2 = 120 degrees.

For an ext detailed information regarding geometry, hybridization, and lewis structure of SO2, you should also refer come the article on the lewis framework of SO2.

Polar and Non-Polar Compounds

We all should recognize that as soon as two atoms kind a bond, they usually share electron from every other.

And also, that is important to save in mind the two different atoms carry out not same share the electron of every other. That is because of the electronegativity difference.

The atom with more electronegativity attracts the pair of external inspection electrons towards itself as compared to the atom the lesser electronegativity.

As every the studies already done, the bond formed in between two atom is polar covalent if the electronegativity difference lies in between 0.5 and also 1.6.

In this bond, the facility of negative charge does not lie in the center. It would certainly be in ~ the end of an atom with greater electronegativity.

And if the electronegativity distinction is lesser than 0.5, the link is non-polar covalent. Whereas, if the electronegativity distinction is above 2, the bond is ionic.

For example, in the case of SO2, Oxygen has a higher electronegativity 보다 Sulfur and it makes it polar. The electronegativity that Sulfur is 2.58 conversely, the electronegativity that Oxygen is 3.44.

And in the situation of NaCl, the Chlorine atom has actually a greater electronegativity than Sodium, because of which the Chlorine atom pulls the electron shared pair towards itself.

If you space a college student of science, the is very helpful come remember that as you relocate right in the regular table the chemistry, the electronegativity of facets gets higher.

Also, together you move up in the routine table, the electronegativity of the elements gets higher.

Thus, if you want to check if a molecule is polar or not.

You have to note under the value of electronegativity of atoms connected in the molecule, the variety of lone pairs and bonds.

And the as whole geometrical shape of the molecule. This info is sufficient to conclude whether the molecule is polar or non-polar.


In this article, ns tried come cover the polarity the sulfur dioxide, and the determinants that influence the polarity, how to examine the polarity of a molecule v the information required to conclude.

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I hope, i cleared her all doubts concerning the polarity the SO2 and additionally made you understand the fundamentals the the polar and non-polar bonds.