# Br2 Lewis structure

Br2 (bromine) has two bromine atoms.

In the Br2 Lewis structure, there is a single bond between the two bromine atoms, and on each bromine atom, there are three lone pairs.

Contents

## Steps

Use these steps to correctly draw the Br2 Lewis structure:

#1 First draw a rough sketch
#2 Mark lone pairs on the atoms
#3 Calculate and mark formal charges on the atoms, if required

Let’s discuss each step in more detail.

### #1 First draw a rough sketch

• First, determine the total number of valence electrons

In the periodic table, bromine lies in group 17. Hence, bromine has seven valence electrons.

Since Br2 has two bromine atoms, so…

Valence electrons of two bromine atoms = 7 × 2 = 14

And the total valence electrons = 14

• Second, find the total electron pairs

We have a total of 14 valence electrons. And when we divide this value by two, we get the value of total electron pairs.

Total electron pairs = total valence electrons ÷ 2

So the total electron pairs = 14 ÷ 2 = 7

• Third, determine the central atom

Here, there are only two atoms and both atoms are bromine, so we can assume any one as the central atom.

Let’s assume that the central atom is right bromine.

• And finally, draw the rough sketch

### #2 Mark lone pairs on the atoms

Here, we have a total of 7 electron pairs. And one Br — Br bond is already marked. So we have to only mark the remaining six electron pairs as lone pairs on the sketch.

Also remember that bromine is a period 4 element, so it can keep more than 8 electrons in its last shell.

Always start to mark the lone pairs from outside atoms. Here, the outside atom is left bromine.

So for each bromine, there are three lone pairs.

Mark the lone pairs on the sketch as follows:

### #3 Calculate and mark formal charges on the atoms, if required

Use the following formula to calculate the formal charges on atoms:

Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons

For each bromine atom, formal charge = 7 – 6 – ½ (2) = 0

Here, both bromine atoms do not have charges, so no need to mark the charges.

In the above structure, you can see that the central atom (right bromine) forms an octet. And the outside atom (left bromine) also forms an octet. Hence, the octet rule is satisfied.

Therefore, this structure is the stable Lewis structure of Br2.

Next: H2Se Lewis structure