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

Lewis Structure of NSF

Ready to learn how to draw the lewis structure of NSF?


Here, I have explained 6 simple steps to draw the lewis dot structure of NSF (along with images).

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

Lewis structure of NSF contains a double bond between the Nitrogen (N) & Sulfur (S) atom and a single bond between the Nitrogen (N) and Fluorine (F) atom. The Nitrogen atom (N) is at the center and it is surrounded by Sulfur and Fluorine atoms. The Nitrogen has 1 lone pair, Sulfur has 2 lone pairs and the Fluorine has 3 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 NSF).

6 Steps to Draw the Lewis Structure of NSF

Step #1: Calculate the total number of valence electrons

Here, the given molecule is NSF. In order to draw the lewis structure of NSF, first of all you have to find the total number of valence electrons present in the NSF 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 NSF

  • For Nitrogen:

Nitrogen is a group 15 element on the periodic table.

Hence, the valence electrons present in nitrogen is 5 (see below image).

  • For Sulfur:

Sulfur is a group 16 element on the periodic table.

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

  • For Fluorine: 

Fluorine is a group 17 element on the periodic table.

Hence, the valence electrons present in fluorine is 7 (see below image).

Hence in a NSF molecule, 

Valence electrons given by Nitrogen (N) atom = 5
Valence electrons given by Sulfur (S) atom = 6
Valence electrons given by Fluorine (F) atom = 7
So, total number of Valence electrons in NSF molecule = 5 + 6 + 7 = 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). [1]

Here in the NSF molecule, if we compare the nitrogen atom (N), sulfur atom (S) and fluorine (F) atom, then the nitrogen is less electronegative than sulfur and fluorine.

So, nitrogen should be placed in the center and the sulfur and fluorine atoms will surround it.

step 1

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

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

step 2

These pairs of electrons present between the Nitrogen (N), Sulfur (S) and Fluorine (F) atoms form a chemical bond, which bonds these atoms with each other in a NSF 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 NSF, the outer atoms are sulfur atom and fluorine atom.

So now, you have to complete the octet on these atoms (because sulfur and fluorine both require 8 electrons to have a complete outer shell).

step 3

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

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

But there are total 18 valence electrons in NSF 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 atom (i.e nitrogen) has an octet or not. 

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

step 5

As you can see from the above image, the central atom (i.e nitrogen) has only 6 electrons. So it does not fulfill the octet rule.

Now, in order to fulfill the octet of nitrogen atom, we have to move the electron pair from the outer atom (i.e sulfur atom) to form a double bond.

step 6

Now you can see from the above image that the central atom (i.e nitrogen), 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 nitrogen atom (N), sulfur atom (S) as well as fluorine atom (F).

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

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

step 7
  • For Nitrogen:
    Valence electrons = 5 (as it is in group 15)
    Nonbonding electrons = 2
    Bonding electrons = 6
  • For Sulfur:
    Valence electron = 6 (as it is in group 16)
    Nonbonding electrons = 4
    Bonding electrons = 4
  • For Fluorine:
    Valence electron = 7 (as it is in group 17)
    Nonbonding electrons = 6
    Bonding electrons = 2
Formal charge=Valence electronsNonbonding electrons(Bonding electrons)/2

So you can see above that the formal charges on nitrogen, sulfur as well as fluorine are “zero”.

Hence, there will not be any change in the above structure and the above lewis structure of NSF is the final stable structure only.

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

nsf lewis structure

Related lewis structures for your practice:
Lewis Structure of C2H4Br2
Lewis Structure of AlBr3
Lewis Structure of AlF3
Lewis Structure of IBr
Lewis Structure of SeCl4

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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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