Lewis Structure, Molecular Geometry, Hybridization, and Polarity for ClO3.

ClO3-, often known as chlorine trioxide or chlorate, is a water-soluble monovalent inorganic anion. Although chlorine trioxide is non-combustible in nature, it is prone to exploding when mixed with combustible elements.

The compound’s molecular weight is 83.45 g/mol.

ClO3- looks to be a moist substance, primarily a solid with moisture.

A redox reaction between chlorine and sodium hydroxide can produce this compound:

3Cl2​(g)​     +   6OH−(aq)   ​ ——>   5Cl−(aq)   ​+    ClO3−(aq)   ​+    3H2​O(l)​

If you’re wondering what a Redox reaction is, it’s a type of reaction in which the oxidation status of atoms is changed.

The modifications that occurred to the Chlorine atom can be seen here.

Chlorates have the property of being strong oxidizers, hence they should be maintained away from materials that are easily oxidised.

As a result, any combustible material, such as sugar or charcoal, should not be introduced near the ClO3- combination.

When chlorine is combined with heated metal hydroxides, a reaction occurs that produces metal chlorates:

3Cl2   +   6KOH    ——>   5KCl   +   KClO3-   +   3H2O

Chlorates are highly hazardous in nature, however they generate chlorides during reactions, which are not harmful.

Now that we’ve learned a little bit about chlorates and how they’re made, let’s look at their Lewis structure and geometry.

Lewis Structure (ClO3)

If you wish to learn more about the compound, you must first comprehend Lewis’ structure.

When we study Lewis’ structure, we learn about the creation of bonds and the positions of various atoms in the plane.

Lewis’ structure is nothing more than a visual representation of how bonds are produced and positioned in a molecule.

Let’s have a look at the Lewis structure of ClO3- one step at a time.

  1. The total number of valence electrons in the chemical must first be determined.

Chlorine has seven valence electrons. Because Chlorine has only one atom, the total valence electrons are 7*1 = 7.

Oxygen has six valence electrons. Because there are three oxygen atoms, the total valence electrons are 6*3 = 18.

This molecule is an anion, as we mentioned in the introduction section. As a result of electron receiving, one of the oxygen atoms has a negative charge.

It’s the same as one valence electron.

To find the compound’s total valence electrons, add the electrons of oxygen, chlorine, and one negative charge, which is =7+18+1 = 26.

  1. Now we’ll learn about the available lone pairings.

Add all the pi and sigma bonds the molecule makes with lone electrons to get the total number of valence pairs.

Because a pair can be formed with the help of two electrons, we will divide the total number of valence electrons by two to find the valence pairs.

There are a total of 13 pairs here.

  1. Figure out what the central atom is.

In the beginning phase, the core atom of this chemical is Chlorine, and there are three bonds formed between Chlorine and Oxygen.

After the initial bonds are formed, the picture displays the lone pair of electrons on the other atoms.

To complete its octet, each oxygen atom has three lone pairs. So there are 9 total lone pairs on oxygen alone.

Because there are three bonds, we only have one lone pair remaining after 9 lone pairs on oxygen, which is assigned to Chlorine.

  1. Charges must be balanced.

We’ll have to balance the charges to make the compound stable.

This will be accomplished by altering the atoms’ bonding.

The initial single bond has now been transformed to a double bond, resulting in a reduction in the charge on Chlorine and Oxygen.

We’ll have to change the other single bonds into double bonds as well to make it more stable.

In the entire facility, there is now only one charge that is acceptable.

It’s possible that you’ll wonder why Chlorine has 12 electrons. This is due to the fact that chlorine can take more than eight electrons. This is due to the fact that the 3d orbital is vacant in its electrical form and can accept extra electrons.

As a result, this is the compound’s most balanced Lewis structure.

This was a little confusing, but we hope you got the hang of it. Now let’s look at how this molecule can be hybridised.

Lewis structure of ClO3

The ClO3- has an sp3 hybridization.

What is the significance of determining a compound’s hybridization?

Hybridization is crucial because it allows us to determine the compound’s most stable structure and geometry. The atomic orbitals are combined together to create new hybrid orbitals with varied energies and shapes.

This is what distinguishes a compound, and we learn about its properties, structures, and geometries as a result. We may calculate ClO3- hybridization using the following formula:

GA + (VE – V – C)/2 = Hybridization

GA denotes a group of atoms linked to the centre atom, VE denotes valence electrons on the central atom, V denotes the central atom’s valency, and C denotes any charge on the molecule.

Because there are three double bonds between chlorine and oxygen, the centre atom in ClO3- has a valency of 6. Chlorine has seven valence electrons. The number of atoms connected to chlorine is three, and the charge is negative.


H = 3 + (7 – 6 – (-1))/2

H = 3 + (1 + 1)/2

H = 3 + 2/2

H = 3 + 1

H = 4

The sp3 hybridization is indicated by the value 4.

ClO3-Molecular Geometry

We can move on to the molecular geometry of this chemical after learning about hybridization and Lewis structure.

However, in order to fully comprehend its structure, we must first understand the theory that aids us in determining the shape of any molecule.

The VSEPR theory is the name of this theory.

The shape of the compound is revealed by Lewis’ structure, but only in a 2D viewpoint.

VSEPR theory is required if you wish to know how the compound will appear in 3D or in a planar representation.

We can also determine the bond angles and lengths of compounds using the VSEPR theory. Let’s figure out the structure of ClO3-, the compound we’re studying.

The A, X, and E symbols are used in the general formula.

Let’s plug our compound into this equation.

Chlorine is A, Oxygen is X, and E is the number of lone pairs on the centre atom, which is Chlorine in this example.

If the values are entered correctly, the formula will be AX3E. Find the shape that corresponds to AX3E in the diagram above. It’s called a Trigonal Pyramid.

This derivation can also be used to determine the bond angle.

The binding angle between the oxygen atom and the chlorine atom is approximately 109 degrees. The repulsion between lone pairs of electrons and bound pairs causes this angle.

Now that we’ve learnt about the molecular structure of the chemical, let’s look at the polarity of ClO3-.

ClO3- has a polarity.

Any compound’s polarity is simply charge separation, which results in a significant dipole moment. The atoms in a polar compound have a partial charge.

Furthermore, the geometry of a polar molecule is not symmetric.

Because ClO3- does not have a symmetric geometry, we may simply classify it as a polar molecule.

Putting it all together in a nutshell

Now that we’ve come to the end of our talk, let’s take a brief look back at all we’ve learned about this compound.

In nature, ClO3- is an inorganic anion.

One of the surrounding oxygen atoms has a negative charge.

The structure contains three double bonds.

The outer shell of the chlorine atom possesses more than 8 electrons.

The substance has a polar nature.

This compound’s hybridization is sp3.

This chemical has a trigonal pyramidal molecular shape.

We hope that your understanding of this substance has improved.

If you have any questions or concerns, please contact our staff, and we will respond with possible solutions.

Thank you for taking the time to read this!

Read more: Strong or Weak Intermolecular Forces in CO2

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.


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