Lewis Structure of S2O (With 6 Simple Steps to Draw!)

Lewis Structure of S2O

I’m super excited to teach you the lewis structure of S2O in just 6 simple steps.

Infact, I’ve also given the step-by-step images for drawing the lewis dot structure of S2O molecule.

So, if you are ready to go with these 6 simple steps, then let’s dive right into it!

Lewis structure of S2O (or Disulfur monoxide) contains two double bonds between the Sulfur-Sulfur atoms and Sulfur-Oxygen atoms. One Sulfur atom is at the center and it is surrounded by other Sulfur atom and Oxygen atom. The central Sulfur atom has 1 lone pair while the outer Sulfur & Oxygen atoms have 2 lone pairs.

Let’s draw and understand this lewis dot structure step by step.

(Note: Take a pen and paper with you and try to draw this lewis structure along with me. I am sure you will definitely learn how to draw lewis structure of S2O).

6 Steps to Draw the Lewis Structure of S2O

Step #1: Calculate the total number of valence electrons

Here, the given molecule is S2O (disulfur monoxide). In order to draw the lewis structure of S2O, first of all you have to find the total number of valence electrons present in the S2O molecule.
(Valence electrons are the number of electrons present in the outermost shell of an atom).

So, let’s calculate this first.

Calculation of valence electrons in S2O

  • For Sulfur:

Sulfur is a group 16 element on the periodic table. [1]

Hence, the valence electrons present in sulfur is 6 (see below image).

  • For Oxygen:

Oxygen is also a group 16 element on the periodic table. [2]

Hence, the valence electron present in oxygen is also 6 (see below image).

Hence in a S2O molecule, 

Valence electrons given by each Sulfur (S) atom = 6
Valence electrons given by Oxygen (O) atom = 6
So, total number of Valence electrons in S2O molecule = 6(2) + 6 = 18

Step #2: Select the center atom

While selecting the atom, always put the least electronegative atom at the center. 

(Remember: Fluorine is the most electronegative element on the periodic table and the electronegativity decreases as we move right to left in the periodic table as well as top to bottom in the periodic table). [3]

Here in the S2O molecule, if we compare the sulfur atom (S) and oxygen atom (O), then the sulfur is less electronegative than oxygen.

So, one of the sulfur should be placed in the center and the remaining sulfur and oxygen atom will surround it.

step 1

Step #3: Put two electrons between the atoms to represent a chemical bond

Now in the above sketch of S2O molecule, put the two electrons (i.e electron pair) between each sulfur atom and oxygen atom to represent a chemical bond between them.

step 2

These pairs of electrons present between the atoms form a chemical bond, which bonds these atoms with each other in a S2O molecule.

Step #4: Complete the octet (or duplet) on outside atoms. If the valence electrons are left, then put the valence electrons pair on the central atom

Don’t worry, I’ll explain!

In the Lewis structure of S2O, the outer atoms are sulfur atom and oxygen atom.

So now, you have to complete the octet on these outer atoms.

step 3

Now, you can see in the above image that both the sulfur and oxygen atoms form an octet.

Also, only 16 valence electrons of S2O molecule are used in the above structure.

But there are total 18 valence electrons in S2O molecule (as calculated in step #1).

So the number of electrons left to be kept on the central atom = 18 – 16 = 2.

So let’s keep these two electrons (i.e 1 electron pair) on the central atom.

step 4

Now, let’s move to the next step.

Step #5: Check whether the central atom has octet or not. If it does not have an octet, then move the electron pair from the outer atom to form a double bond or triple bond

In this step, we have to check whether the central sulfur atom has an octet or not. 

In simple words, we have to check whether the central Sulfur (S) atom has 8 electrons or not.

step 5

Now you can see from the above image that the central atom (i.e sulfur), is having 8 electrons. So it fulfills the octet rule.

Step #6: Final step – Check the stability of lewis structure by calculating the formal charge on each atom

Now, you have come to the final step and here you have to check the formal charge on oxygen atom (O) as well as each sulfur atom (S).

For that, you need to remember the formula of formal charge;

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

step 6
  • For outer Sulfur:
    Valence electron = 6 (as it is in group 16)
    Nonbonding electrons = 4
    Bonding electrons = 4
  • For central Sulfur:
    Valence electron = 6 (as it is in group 16)
    Nonbonding electrons = 2
    Bonding electrons = 6
  • For Oxygen:
    Valence electrons = 6 (as it is in group 16)
    Nonbonding electrons = 6
    Bonding electrons = 2
Formal charge=Valence electronsNonbonding electrons(Bonding electrons)/2
Outer S=644/2=0
Central S=626/2=+1

So you can see above that the formal charge on central sulfur is +1 and the formal charge on the oxygen atom is -1.

This indicates that the above lewis structure of S2O is not stable and so we have to minimize the charges to get a more stable lewis structure.

This can be done by shifting the lone pair from negatively charged oxygen atom to the positively charged sulfur atom to form a bond.

step 7

Now, in the above structure, you can see that the charges are minimized and the above lewis structure of S2O is the final stable structure.

Each electron pair (:) in the lewis dot structure of S2O represents the single bond ( | ). So the above lewis dot structure of S2O can also be represented as shown below.

s2o lewis structure

Related lewis structures for your practice:
Lewis Structure of BrCl3
Lewis Structure of NO2Cl
Lewis Structure of TeF4
Lewis Structure of ClF
Lewis Structure of SO 

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Jay is an educator and has helped more than 100,000 students in their studies by providing simple and easy explanations on different science-related topics. With a desire to make learning accessible for everyone, he founded Knords Learning, an online learning platform that provides students with easily understandable explanations.

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