What is the Charge on SO2 (Sulfur dioxide)? And Why?

The Charge of SO2 (Sulfur dioxide) is 0.

But the question is how can you say that the charge on SO2 (Sulfur dioxide) is 0?

Well you can say this by calculating its formal charge.

So let’s calculate the formal charge of SO2 (Sulfur dioxide).

If you are a visual learner like me, then here is a short two minute video for you.

Calculating the formal charge of SO2 using lewis structure

In order to calculate the formal charge on SO2 (Sulfur dioxide), you should know the Lewis dot structure of SO2 (Sulfur dioxide).

Here is the lewis structure of SO2.

Now using the above lewis structure of SO2, you have to find the formal charge on each atom that is present in the SO2 molecule.

For calculating the formal charge, you need to remember this formula;

Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2

You can see the bonding and nonbonding electrons of SO2 from the image given below.

So now let’s calculate the formal charge on each individual atom present in SO2.

Formal charge on Sulfur atom:
Valence electrons = 6 (as it is in group 16 on periodic table) ^[1]
Nonbonding electrons = 2
Bonding electrons = 8

So according to the formula of formal charge, you will get;

Formal charge on Sulfur = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 6 – 2 – (8/2) = 0

So the formal charge on sulfur atom is 0.

Formal charge on Oxygen atom:
Valence electrons = 6 (as it is in group 16 on periodic table) ^[2]
Nonbonding electrons = 4
Bonding electrons = 4

So according to the formula of formal charge, you will get;

Formal charge on Oxygen = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 6 – 4 – (4/2) = 0

So the formal charge on oxygen atom is 0.

Now you can see that all the atoms of SO2 have 0 formal charge. 

This indicates that the overall SO2 (Sulfur dioxide) molecule also has 0 charge and hence it is a neutral molecule.

I hope you have understood the above calculations for the formal charge of SO2 (Sulfur dioxide). 

Check out some other related topics for your practice.

Related topics:
Charge of Arsenic (As)
Charge on Sulfuric acid (H2SO4)
Charge on Nitric acid (HNO3)
Charge on Acetic acid (CH3COOH)
Charge of O3 (Ozone)