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.

Alternative method: Lewis structure of SbCl₃

Rough sketch

• 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

Learn how to find: Antimony valence electrons and Chlorine valence electrons

• 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

Lone pair

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:

Formal charge

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.

Final structure

The final structure of SbCl₃ comprises a central antimony atom linked to three chlorine atoms through single covalent bonds. In this arrangement, the antimony atom satisfies the octet rule by forming three bonding pairs and retaining one lone pair. Within this layout, each of the three chlorine atoms successfully reaches a stable octet by maintaining three lone pairs alongside its single shared bond. This configuration represents the most stable state for the molecule because it results in a formal charge of zero for every atom involved. Accordingly, this specific electronic distribution serves as the definitive and most accurate Lewis representation of antimony trichloride.

Next: C₂H₄F₂ Lewis structure

External video

• Lewis Dot Structure for SbCl3 (and Molecular Geometry) – YouTube • Wayne Breslyn

External links

• https://www.chegg.com/homework-help/draw-lewis-dot-structures-following-sbcl3-b-alf63-c-pcl5-chapter-8-problem-32e-solution-9781133611509-exc
• https://www.answers.com/Q/What_is_the_dot_structure_for_SbCl3
• https://www.numerade.com/questions/write-lewis-formulas-for-the-following-a-mathrmsbcl_3-b-icn-c-mathrmicl_3-d-mathrmif_5/