CCl2F2 (dichlorodifluoromethane) has one carbon atom, two chlorine atoms, and two fluorine atoms.
In the CCl2F2 Lewis structure, there are four single bonds around the carbon atom, with two chlorine atoms and two fluorine atoms attached to it, and on each chlorine and fluorine atom, there are three lone pairs.
Steps
Use these steps to correctly draw the CCl2F2 Lewis structure:
#1 First draw a rough sketch
#2 Mark lone pairs on the atoms
#3 Calculate and mark formal charges on the atoms, if required
Let’s discuss each step in more detail.
#1 First draw a rough sketch
- First, determine the total number of valence electrons
In the periodic table, carbon lies in group 14, and both chlorine and fluorine lie in group 17.
Hence, carbon has four valence electrons, both chlorine and fluorine have seven valence electrons.
Since CCl2F2 has one carbon atom, two chlorine atoms, and two fluorine atoms, so…
Valence electrons of one carbon atom = 4 × 1 = 4
Valence electrons of two chlorine atoms = 7 × 2 = 14
Valence electrons of two fluorine atoms = 7 × 2 = 14
And the total valence electrons = 4 + 14 + 14 = 32
Learn how to find: Carbon valence electrons, Chlorine valence electrons, and Fluorine valence electrons
- Second, find the total electron pairs
We have a total of 32 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 = 32 ÷ 2 = 16
- Third, determine the central atom
We have to place the least electronegative atom at the center.
Since carbon is less electronegative than chlorine and fluorine, assume that the central atom is carbon.
Therefore, place carbon in the center and chlorine and fluorine on either side.
- And finally, draw the rough sketch
#2 Mark lone pairs on the atoms
Here, we have a total of 16 electron pairs. And four bonds are already marked. So we have to only mark the remaining twelve electron pairs as lone pairs on the sketch.
Also remember that both (carbon and fluorine) are the period 2 elements, so they can not keep more than 8 electrons in their 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 and fluorines.
So for each chlorine and fluorine, there are three lone pairs, and for carbon, there is zero lone pair because all twelve electron pairs are over.
Mark the lone pairs on the sketch as follows:
#3 Calculate and mark formal charges on the atoms, if required
Use the following formula to calculate the formal charges on atoms:
Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons
For carbon atom, formal charge = 4 – 0 – ½ (8) = 0
For each chlorine atom, formal charge = 7 – 6 – ½ (2) = 0
For each fluorine atom, formal charge = 7 – 6 – ½ (2) = 0
Here, the atoms do not have charges, so no need to mark the charges.
In the above structure, you can see that the central atom (carbon) forms an octet. And the outside atoms (chlorines and fluorines) also form an octet. Hence, the octet rule is satisfied.
Therefore, this structure is the stable Lewis structure of CCl2F2.
Next: P4 Lewis structure
External links
- https://lambdageeks.com/ccl2f2-lewis-structure/
- https://topblogtenz.com/cf2cl2-lewis-structure-molecular-geometry-and-polar-or-nonpolar/
- https://www.chemistryscl.com/general/dichlorodifluoromethane-CCl2F2-lewis-structure/index.php
- https://oneclass.com/homework-help/chemistry/7028769-ccl2f2-lewis-structure.en.html
Deep
Learnool.com was founded by Deep Rana, who is a mechanical engineer by profession and a blogger by passion. He has a good conceptual knowledge on different educational topics and he provides the same on this website. He loves to learn something new everyday and believes that the best utilization of free time is developing a new skill.