Lewis Structure of SBr2 (With 6 Simple Steps to Draw!) (2024)

Lewis structure of SBr2 contains two single bonds between the Sulfur (S) atom and each Bromine (Br) atom. The Sulfur atom (S) is at the center and it is surrounded by 2 Bromine atoms (Br). The Sulfur atom has 2 lone pairs and both the Bromine atoms have 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 SBr2).

6 Steps to Draw the Lewis Structure of SBr2

Step #1: Calculate the total number of valence electrons

Here, the given molecule is SBr2 (sulfur dibromide). In order to draw the lewis structure of SBr2, first of all you have to find the total number of valence electrons present in the SBr2 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 SBr2

• 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 Bromine:

Bromine is a group 17 element on the periodic table. ^[2]

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

Hence in a SBr2 molecule,

Valence electrons given by Sulfur (S) atom = 6
Valence electrons given by each Bromine (Br) atom = 7
So, total number of Valence electrons in SBr2 molecule = 6 + 7(2) = 20

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 SBr2 molecule, if we compare the sulfur atom (S) and bromine atom (Br), then the sulfur is less electronegative than bromine.

So, sulfur should be placed in the center and the remaining 2 bromine atoms will surround it.

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

Now in the above sketch of SBr2 molecule, put the two electrons (i.e electron pair) between each sulfur atom and bromine atom to represent a chemical bond between them.

These pairs of electrons present between the Sulfur (S) and Bromine (Br) atoms form a chemical bond, which bonds the sulfur and bromine atoms with each other in a SBr2 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 SBr2, the outer atoms are bromine atoms.

So now, you have to complete the octet on these bromine atoms (because bromine requires 8 electrons to have a complete outer shell).

Now, you can see in the above image that all the bromine atoms form an octet.

Also, only 16 valence electrons of SBr2 molecule are used in the above structure.

But there are total 20 valence electrons in SBr2 molecule (as calculated in step #1).

So the number of electrons left to be kept on the central atom = 20 – 16 = 4.

So let’s keep these four electrons (i.e 2 electron pairs) on the central atom.

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 sulfur) has an octet or not.

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

As you can see from the above image, the central atom (i.e sulfur), has 8 electrons. So it fulfills the octet rule and the sulfur atom is stable.

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 sulfur atom (S) as well as each bromine atom (Br).

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

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

• For Sulfur:
  Valence electron = 6 (as it is in group 16)
  Nonbonding electrons = 4
  Bonding electrons = 4
• For Bromine:
  Valence electron = 7 (as it is in group 17)
  Nonbonding electrons = 6
  Bonding electrons = 2

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

Hence, there will not be any change in the above structure and the above lewis structure of SBr2 is the final stable structure only.

Each electron pair (:) in the lewis dot structure of SBr2 represents the single bond ( | ). So the above lewis dot structure of SBr2 can also be represented as shown below.

Related lewis structures for your practice:
Lewis Structure of HOCl
Lewis Structure of C6H6 (Benzene)
Lewis Structure of NBr3
Lewis Structure of SeF4
Lewis Structure of H3PO4

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