ClF (chlorine monofluoride) has one chlorine atom and one fluorine atom. In the lewis structure of ClF, there is a single bond between the chlorine and fluorine atom, and on both chlorine and fluorine atoms, there are three lone pairs.
Here’s how you can draw the ClF lewis structure step by step.
Step #1: draw sketch
Step #2: mark lone pairs
Step #3: mark charges (if there are)
Let’s break down each step in detail.
#1 Draw Sketch
- First, determine the total number of valence electrons
Hence, both chlorine and fluorine have seven valence electrons.
Since ClF has one chlorine atom and one fluorine atom, so…
Valence electrons of one chlorine atom = 7 × 1 = 7
Valence electrons of one fluorine atom = 7 × 1 = 7
And the total valence electrons = 7 + 7 = 14
- Second, find the total electron pairs
We have a total of 14 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 = 14 ÷ 2 = 7
- 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.
- And finally, draw the rough sketch
#2 Mark Lone Pairs
Here, we have a total of 7 electron pairs. And one Cl — F bond is already marked. So we have to only mark the remaining six 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 atom is fluorine.
So for each atom, there are three lone pairs.
Mark the lone pairs on the sketch as follows:
#3 Mark Charges
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 – 6 – ½ (2) = 0
For 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.
And in the above structure, you can see that the central atom (chlorine) forms an octet. Hence, the octet rule is satisfied.
Therefore, this structure is the stable lewis structure of ClF.
Next: SO Lewis Structure