Lewis structure of ClO4-

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The Lewis structure of ClO₄^– contains one single bond and three double bonds, with chlorine in the center, and four oxygens on either side. The bottom oxygen atom has three lone pairs. The top oxygen atom, left oxygen atom, and right oxygen atom have two lone pairs, and the chlorine atom does not have any lone pair.

Plus, there is a negative (-1) charge on the bottom oxygen atom.

Steps

By using the following steps, you can easily draw the Lewis structure of ClO₄^–:

#1 Draw skeleton
#2 Show chemical bond
#3 Mark lone pairs
#4 Calculate formal charge and check stability (if octet is already completed on central atom)
#5 Convert lone pair and calculate formal charge again (if formal charges are not closer to zero)

Let’s one by one discuss each step in detail.

#1 Draw skeleton

In this step, first calculate the total number of valence electrons. And then, decide the central atom.

• Let’s calculate the total number of valence electrons

We know that… chlorine is a group 17 element and oxygen is a group 16 element. Hence, chlorine has seven valence electrons and oxygen has six valence electrons.

Now ClO₄^– has one chlorine atom and four oxygen atoms.

So the total number of valence electrons = valence electrons of chlorine atom + (valence electrons of oxygen atom × 4)

And ClO₄^– has a negative (-1) charge, so we have to add one more electron.

Therefore, the total number of valence electrons = 7 + 24 + 1 = 32

• Now decide the central atom

The atom with the least electronegative value is placed at the center. By looking at the periodic table, we get the electronegativity values for chlorine and oxygen as follows:

Electronegativity value of chlorine = 3.16
Electronegativity value of oxygen = 3.44

Obviously, chlorine is less electronegative than oxygen. Hence, assume that chlorine is the central atom.

So now, put chlorine in the center and oxygens on either side. And draw the rough skeleton structure for the Lewis structure of ClO₄^– something like this:

Also read: How to draw Lewis structure of CBr₄ (4 steps)

#2 Show chemical bond

Place two electrons between the atoms to show a chemical bond. Since chlorine is surrounded by four oxygens, use eight electrons to show four chemical bonds as follows:

#3 Mark lone pairs

As calculated earlier, we have a total of 32 valence electrons. And in the above structure, we have already used eight valence electrons. Hence, twenty-four valence electrons are remaining.

Two valence electrons represent one lone pair. So twenty-four valence electrons = twelve lone pairs.

Note that chlorine is period 3 element, so it can keep more than 8 electrons in its last shell. And oxygen is a period 2 element, so it can not keep more than 8 electrons in its last shell.

Also, make sure that you start marking these lone pairs on outside atoms first. And then, on the central atom.

The outside atoms are oxygens, so each oxygen will get three lone pairs. And the central atom (chlorine) will not get any lone pair, because all twelve lone pairs are used.

So the Lewis structure of ClO₄^– looks something like this:

In the above structure, you can see that the octet is completed on the central atom (chlorine), and also on the outside atoms. Therefore, the octet rule is satisfied.

Now calculate the formal charge and check the stability of the above structure.

Also read: How to draw Lewis structure of SeO₂ (6 steps)

#4 Calculate formal charge and check stability

The following formula is used to calculate the formal charges on atoms:

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

Collect the data from the above structure and then, write it down below as follows:

• For chlorine atom

Valence electrons = 7
Nonbonding electrons = 0
Bonding electrons = 8

Formal charge = 7 – 0 – ½ (8) = +3

• For each oxygen atom

Valence electrons = 6
Nonbonding electrons = 6
Bonding electrons = 2

Formal charge = 6 – 6 – ½ (2) = -1

Mention the formal charges of atoms on the structure. So the Lewis structure of ClO₄^– looks something like this:

In the above structure, you can see that the formal charges of atoms are not closer to zero. Therefore, convert lone pair and calculate formal charge again.

Also read: How to draw Lewis structure of ICl₄^– (4 steps)

#5 Convert lone pair and calculate formal charge again

As mentioned earlier, chlorine is a period 3 element, so it can keep more than 8 electrons in its last shell.

So convert one lone pair from the three oxygen atoms to make a new bond with the chlorine atom. And then, the Lewis structure of ClO₄^– looks something like this:

Now one last thing we need to do is, calculate the formal charge again and check the stability of the above structure.

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

Collect the data from the above structure and then, write it down below as follows:

• For chlorine atom

Valence electrons = 7
Nonbonding electrons = 0
Bonding electrons = 14

Formal charge = 7 – 0 – ½ (14) = 0

• For top oxygen, left oxygen, and right oxygen atom

Valence electrons = 6
Nonbonding electrons = 4
Bonding electrons = 4

Formal charge = 6 – 4 – ½ (4) = 0

• For bottom oxygen atom

Valence electrons = 6
Nonbonding electrons = 6
Bonding electrons = 2

Formal charge = 6 – 6 – ½ (2) = -1

Mention the formal charges of atoms on the structure. So the Lewis structure of ClO₄^– looks something like this:

In the above structure, you can see that the formal charges of atoms are closer to zero. Therefore, this is the most stable Lewis structure of ClO₄^–.

And each horizontal line drawn in the above structure represents a pair of bonding valence electrons.

Now ClO₄^– is an ion having a negative (-1) charge, so draw brackets around the above Lewis structure and mention that charge on the top right corner. And then, the Lewis structure of ClO₄^– looks something like this:

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Related

• Lewis structure of CBr₄
• Lewis structure of SeO₂
• Lewis structure of ICl₄^–
• Lewis structure of SiCl₄
• Lewis structure of SiF₄

External video

• ClO4- Lewis Structure – How to Draw the Lewis Structure for ClO4- (Perchlorate Ion) – YouTube • Wayne Breslyn

External links

• Lewis Structure for ClO4- (Perchlorate Ion) – The University of Maryland
• ClO4- Lewis Structure (Perchlorate ion) – Chemistry School
• Lewis Structure of ClO4- [with video and free guide] – AceOrganicChem
• ClO4- Lewis Structure in 5 Steps (With Images) – Pediabay
• ClO4- lewis structure, molecular geometry, bond angle, hybridization – Topblogtenz
• Lewis Dot of the Perchlorate Ion ClO4- – Kent’s Chemistry
• How would you draw the Lewis Structure for ClO4 – Quora
• VSEPR calculation for perchlorate, [ClO4] – University of Sheffield
• ClO4- Lewis Structure (Perchlorate Ion) – Pinterest
• Chemical Bonding: ClO4- Lewis Structure – The Geoexchange
• Draw the Lewis structure for ClO₄^–. Is it necessary to employ an expanded valence shell? – Homework.Study.com
• Draw the Lewis structure for the perchlorate ion – Chegg
• Lewis Dot Structure for ClO4- – Physics Forums
• Formal Charge of Perchlorate (ClO4-) – Chemistry Learner
• Draw the Lewis structure of perchlorate (ClO4-) and draw all possible resonance structures of it – Numerade
• what is the lewis structure of CLO4- – Bartleby
• What is the formal charge of Cl− in the perchlorate ion, ClO−4, assuming the Cl−O bonds are all single bonds? – Wyzant
• Why does ClO₄^– only have 3 double bonds? – Chemistry Stack Exchange