So you have seen the above image by now, right?
Let me explain the above image in short.
NS2 lewis structure has a Nitrogen atom (N) at the center which is surrounded by two Sulfur atoms (S). There is 1 double bond and 1 single bond between the Nitrogen atom (N) and each Sulfur atom (S). There is 1 lone pair on Nitrogen atom (N), 2 lone pairs on double bonded Sulfur atom (S) and 3 lone pairs on single bonded Sulfur atom (S).
If you haven’t understood anything from the above image of NS2 lewis structure, then just stick with me and you will get the detailed step by step explanation on drawing a lewis structure of NS2.
So let’s move to the steps of drawing the lewis structure of NS2.
Steps of drawing NS2 lewis structure
Step 1: Find the total valence electrons in NS2 molecule
In order to find the total valence electrons in NS2 molecule, first of all you should know the valence electrons present in nitrogen atom as well as sulfur atom.
(Valence electrons are the electrons that are present in the outermost orbit of any atom.)
Here, I’ll tell you how you can easily find the valence electrons of nitrogen as well as sulfur using a periodic table.
Total valence electrons in NS2 molecule
→ Valence electrons given by nitrogen atom:
Nitrogen is a group 15 element on the periodic table.  Hence the valence electrons present in nitrogen is 5.
You can see the 5 valence electrons present in the nitrogen atom as shown in the above image.
→ Valence electrons given by sulfur atom:
Sulfur is a group 16 element on the periodic table.  Hence the valence electrons present in sulfur is 6.
You can see the 6 valence electrons present in the sulfur atom as shown in the above image.
Total valence electrons in NS2 molecule = valence electrons given by 1 nitrogen atom + valence electrons given by 2 sulfur atoms = 5 + 6(2) = 17.
Step 2: Select the central atom
For selecting the center atom, you have to remember that the atom which is less electronegative remains at the center.
Now here the given molecule is NS2 and it contains nitrogen atom (N) and sulfur atoms (S).
You can see the electronegativity values of nitrogen atom (N) and sulfur atom (S) in the above periodic table.
If we compare the electronegativity values of nitrogen (N) and sulfur (S) then the nitrogen atom is less electronegative.
So here the nitrogen atom (N) is the center atom and the sulfur atoms (S) are the outside atoms.
Step 3: Connect each atoms by putting an electron pair between them
Now in the NS2 molecule, you have to put the electron pairs between the nitrogen atom (N) and sulfur atoms (S).
This indicates that the nitrogen (N) and sulfur (S) are chemically bonded with each other in a NS2 molecule.
Step 4: Make the outer atoms stable. Place the remaining valence electrons pair on the central atom.
Now in this step, you have to check the stability of the outer atoms.
Here in the sketch of NS2 molecule, you can see that the outer atoms are sulfur atoms.
These outer sulfur atoms are forming an octet and hence they are stable.
Also, in step 1 we have calculated the total number of valence electrons present in the NS2 molecule.
The NS2 molecule has a total 17 valence electrons and out of these, only 16 valence electrons are used in the above sketch.
So the number of electrons which are left = 17 – 16 = 1.
You have to put this 1 electron on the central nitrogen atom in the above sketch of NS2 molecule.
Now let’s proceed to the next step.
Step 5: Check the octet on the central atom. If it does not have octet, then shift the lone pair to form a double bond or triple bond.
In this step, you have to check whether the central nitrogen atom (N) is stable or not.
In order to check the stability of the central nitrogen (N) atom, we have to check whether it is forming an octet or not.
Unfortunately, the nitrogen atom is not forming an octet here. Nitrogen has only 5 electrons and it is unstable.
Now to make this nitrogen atom stable, you have to shift the electron pair from the outer sulfur atom so that the nitrogen atom can become more stable.
After shifting this electron pair, the central nitrogen atom will get 2 more electrons and thus its total electrons will become 7.
You can see that nitrogen is not forming an octet (because it has 7 electrons). Now if you will further try to shift the electron pair, then there will be 7 + 2 = 9 electrons.
And nitrogen atom do not have the capacity to hold 9 electrons. Hence the above lewis structure of NS2 (with 7 electrons on nitrogen atom) is stable.
In the above lewis dot structure of NS2, you can also represent each bonding electron pair (:) as a single bond (|). By doing so, you will get the following lewis structure of NS2.
I hope you have completely understood all the above steps.
For more practice and better understanding, you can try other lewis structures listed below.
Try (or at least See) these lewis structures for better understanding:
|SiH2O Lewis Structure
|OF3- Lewis Structure
|PH4+ Lewis Structure
|SHF Lewis Structure
|SeS3 Lewis Structure
|IBr5 Lewis Structure
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. He is a founder of Pediabay and is passionate about helping students through his easily digestible explanations.
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