# SbCl3 Lewis structure

SbCl3 (antimony trichloride) has one antimony atom and three chlorine atoms.

In SbCl3 Lewis structure, there are three single bonds around the antimony atom, with three chlorine atoms attached to it. Each chlorine atom has three lone pairs, and the antimony atom has one lone pair.

Contents

## Steps

Here’s how you can easily draw the SbCl3 Lewis structure step by step:

#1 Draw a rough skeleton structure
#2 Mention lone pairs on the atoms
#3 If needed, mention formal charges on the atoms

Now, let’s take a closer look at each step mentioned above.

### #1 Draw a rough skeleton structure

• First, determine the total number of valence electrons

In the periodic table, antimony lies in group 15, and chlorine lies in group 17.

Hence, antimony has five valence electrons and chlorine has seven valence electrons.

Since SbCl3 has one antimony atom and three chlorine atoms, so…

Valence electrons of one antimony atom = 5 × 1 = 5
Valence electrons of three chlorine atoms = 7 × 3 = 21

And the total valence electrons = 5 + 21 = 26

• Second, find the total electron pairs

We have a total of 26 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 = 26 ÷ 2 = 13

• Third, determine the central atom

We have to place the least electronegative atom at the center.

Since antimony is less electronegative than chlorine, assume that the central atom is antimony.

Therefore, place antimony in the center and chlorines on either side.

• And finally, draw the rough sketch

### #2 Mention lone pairs on the atoms

Here, we have a total of 13 electron pairs. And three Sb — Cl bonds are already marked. So we have to only mark the remaining ten electron pairs as lone pairs on the sketch.

Also remember that antimony is a period 5 element, so it can keep more than 8 electrons in its last shell. And chlorine is a period 3 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 atoms are chlorines.

So for each chlorine, there are three lone pairs, and for antimony, there is one lone pair.

Mark the lone pairs on the sketch as follows:

### #3 If needed, mention formal charges on the atoms

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

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

For antimony atom, formal charge = 5 – 2 – ½ (6) = 0

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

Here, both antimony and chlorine atoms do not have charges, so no need to mark the charges.

In the above structure, you can see that the central atom (antimony) forms an octet. And the outside atoms (chlorines) also form an octet. Hence, the octet rule is satisfied.

Therefore, this structure is the stable Lewis structure of SbCl3.