SCl4 Lewis Structure in 5 Steps (With Images)

So you have seen the above image by now, right?

Let me explain the above image in short.

SCl4 lewis structure has a Sulfur atom (S) at the center which is surrounded by four Chlorine atoms (Cl). There are 4 single bonds between the Sulfur atom (S) and each Chlorine atom (Cl). There is 1 lone pair on the Sulfur atom (S) and 3 lone pairs on all the four Chlorine atoms (Cl).

If you haven’t understood anything from the above image of SCl4 lewis structure, then just stick with me and you will get the detailed step by step explanation on drawing a lewis structure of SCl4.

So let’s move to the steps of drawing the lewis structure of SCl4.

Steps of drawing SCl4 lewis structure

Step 1: Find the total valence electrons in SCl4 molecule

In order to find the total valence electrons in SCl4 molecule, first of all you should know the valence electrons present in sulfur atom as well as chlorine 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 sulfur as well as chlorine using a periodic table.

Total valence electrons in SCl4 molecule

→ Valence electrons given by sulfur atom:

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

→ Valence electrons given by chlorine atom:

Chlorine is group 17 element on the periodic table. ^[2] Hence the valence electrons present in chlorine is 7.

You can see the 7 valence electrons present in the chlorine atom as shown in the above image.

Hence, 

Total valence electrons in SCl4 molecule = valence electrons given by 1 sulfur atom + valence electrons given by 4 chlorine atoms = 6 + 7(4) = 34.

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 SCl4 and it contains sulfur atom (S) and chlorine atoms (Cl).

You can see the electronegativity values of sulfur atom (S) and chlorine atom (Cl) in the above periodic table.

If we compare the electronegativity values of sulfur (S) and chlorine (Cl) then the sulfur atom is less electronegative.

So here the sulfur atom (S) is the center atom and the chlorine atoms (Cl) are the outside atoms.

Step 3: Connect each atoms by putting an electron pair between them

Now in the SCl4 molecule, you have to put the electron pairs between the sulfur atom (S) and chlorine atoms (Cl).

This indicates that the sulfur (S) and chlorine (Cl) are chemically bonded with each other in a SCl4 molecule.

Step 4: Make the outer atoms stable

Now in this step, you have to check the stability of the outer atoms.

Here in the sketch of SCl4 molecule, you can see that the outer atoms are chlorine atoms.

These outer chlorine 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 SCl4 molecule.

The SCl4 molecule has a total 34 valence electrons and out of these, only 32 valence electrons are used in the above sketch.

So the number of electrons which are left = 34 – 32 = 2.

You have to put these 2 electrons on the central sulfur atom in the above sketch of SCl4 molecule.

Now let’s proceed to the next step.

Step 5: Check the stability of lewis structure

Now you have come to the final step in which you have to check the stability of lewis structure of SCl4.

The stability of lewis structure can be checked by using a concept of formal charge.

In short, now you have to find the formal charge on sulfur (S) atom as well as chlorine (Cl) atoms present in the SCl4 molecule.

For calculating the formal charge, you have to use the following formula;

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

You can see the number of bonding electrons and nonbonding electrons for each atom of SCl4 molecule in the image given below.

For Sulfur (S) atom:
Valence electrons = 6 (because sulfur is in group 16)
Bonding electrons = 8
Nonbonding electrons = 2

For Chlorine (Cl) atom:
Valence electron = 7 (because chlorine is in group 17)
Bonding electrons = 2
Nonbonding electrons = 6

From the above calculations of formal charge, you can see that the sulfur (S) atom as well as chlorine (Cl) atom has a “zero” formal charge.

This indicates that the above lewis structure of SCl4 is stable and there is no further change in the above structure of SCl4.

In the above lewis dot structure of SCl4, you can also represent each bonding electron pair (:) as a single bond (|). By doing so, you will get the following lewis structure of SCl4.

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:

About author

Jay Rana

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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