Is SBr2 Polar or Nonpolar? (And Why?)

SBr2 is a POLAR molecule.

But why? 

And how can you say that SBr2 is a polar molecule?

Want to know the reason?
Let’s dive into it!

SBr2 is a POLAR molecule because it has two lone pairs of electrons on the Sulfur atom (S) which causes the entire molecule to bend.
This bending of SBr2 molecule results in asymmetric geometry, which makes the molecule polar.

Let me explain this in detail with the help of SBr2 lewis structure and its 3D geometry.

Why is SBr2 a Polar molecule? (Explained in 2 Steps)

To understand the polar nature of SBr2 molecule, first of all you should know its lewis structure as well as its molecular geometry.

So let’s see this in the steps below.

Step #1: Draw the lewis structure

Here is a skeleton of SBr2 lewis structure and it contains two S-Br bonds.

(Note: If you want to know the steps of drawing the SBr2 lewis dot structure, then visit this article: SBr2 lewis structure, Or you can also watch this short 2 minute video).

So from the above diagram we have come to know that the SBr2 molecule has two S-Br bonds.

Now in the next step we have to check whether these two S-Br bonds are polar or nonpolar.

And we also have to check the molecular geometry of SBr2.

Step #2: Check the bond polarity and molecular geometry

The chemical bonds can be either nonpolar, polar or ionic depending on the difference of the electronegativity values (ΔEN) between the two atoms.

Have a look at the above image.

• If the electronegativity difference (ΔEN) is less than 0.4, then the bond is nonpolar covalent bond.
• If the electronegativity difference (ΔEN) is between 0.4 to 1.7, then the bond is polar covalent bond. 
• If the electronegativity difference (ΔEN) is greater than 1.7, then the bond is an ionic bond. ^{[1] [2] [3] [4] [5]}

Now let’s come to the example of SBr2 molecule. It has two S-Br bonds.

You can see the electronegativity values of Sulfur (S) and Bromine (Br) atoms from the periodic table given below.

From the above image;

• Electronegativity of Sulfur (S) = 2.58 ^[6]
• Electronegativity of Bromine (Br) = 2.96 ^[7]

Now let’s see the polarity of each bond.

For S-Br bond;
The electronegativity difference (ΔEN) = 2.96 – 2.58 = 0.38
This value is less than 0.4, which indicates that the bond between Sulfur (S) and Bromine (Br) is nonpolar.
Hence, each S-Br bond is a nonpolar covalent bond.

But wait, we also have to look at the molecular geometry of SBr2 to know whether it has a symmetric shape or not.

Have a look at this 3D structure of SBr2. The Sulfur atom (S) is at the center and it is surrounded by 2 Bromine atoms (Br).

It also has two lone pairs on the Sulfur atom (S).

Due to the lone pairs on the sulfur atom (S), its molecular geometry becomes asymmetric.

Because of this, there are positive and negative poles of charges on the overall molecule of SBr2.

Hence, the SBr2 molecule is a polar molecule.

I hope you have understood the reason behind the polar nature of SBr2 molecule.

See the polarity of other molecules to make your concepts clear:
Is CHF3 Polar or Nonpolar?
Is SeF4 Polar or Nonpolar?
Is CH2Br2 Polar or Nonpolar?
Is Ammonium ion (NH4+) Polar or Nonpolar?
Is CH3NH2 Polar or Nonpolar?