ClF5 Lewis structure

ClF₅ (chlorine pentafluoride) has one carbon atom, two hydrogen atoms, and one oxygen atom.

In the ClF₅ Lewis structure, there are five single bonds around the chlorine atom, with five fluorine atoms attached to it. Each fluorine atom has three lone pairs, and the chlorine atom has one lone pair.

Alternative method: Lewis structure of ClF₅

Rough sketch

• First, determine the total number of valence electrons

In the periodic table, both chlorine and fluorine lie in group 17.

Hence, both chlorine and fluorine have seven valence electrons.

Since ClF₅ has one chlorine atom and five fluorine atoms, so…

Valence electrons of one chlorine atom = 7 × 1 = 7
Valence electrons of five fluorine atoms = 7 × 5 = 35

And the total valence electrons = 7 + 35 = 42

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

• Second, find the total electron pairs

We have a total of 42 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 = 42 ÷ 2 = 21

• Third, determine the central atom

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

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

Therefore, place chlorine in the center and fluorines on either side.

• And finally, draw the rough sketch

Lone pair

Here, we have a total of 21 electron pairs. And five Cl — F bonds are already marked. So we have to only mark the remaining sixteen electron pairs as lone pairs on the sketch.

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

Always start to mark the lone pairs from outside atoms. Here, the outside atoms are fluorines.

So for each fluorine, there are three lone pairs, and for chlorine, 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 chlorine atom, formal charge = 7 – 2 – ½ (10) = 0

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

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

Final structure

The final structure of ClF₅ shows a central chlorine atom connected to five fluorine atoms through five single covalent bonds. In this arrangement, the chlorine atom utilizes an expanded octet to accommodate twelve electrons, including one lone pair, while each fluorine atom completes its octet with three lone pairs. This configuration is the most stable because it allows all five fluorine atoms to achieve a formal charge of zero, leaving the chlorine atom with a formal charge of zero as well. Consequently, this specific distribution of electrons represents the definitive and stable Lewis representation of chlorine pentafluoride.

Next: C₃H₈ Lewis structure

External video

• ClF5 Lewis Structure – How to Draw the Lewis Structure for ClF5 (Chlorine Pentafluoride) – YouTube • Wayne Breslyn

External links

• https://lambdageeks.com/clf5-lewis-structure/
• https://techiescientist.com/clf5-lewis-structure/
• https://www.thegeoexchange.org/chemistry/bonding/Lewis-Structures/ClF5-lewis-structure.html
• https://sciedutut.com/how-to-draw-clf5-lewis-structure/