CF4 Lewis Structure

CF4 Lewis Structure

CF4 (carbon tetrafluoride) has one carbon atom and four fluorine atoms. In the lewis structure of CF4, there are four single bonds around the fluorine atom, with four fluorine atoms attached to it, and on each fluorine atom, there are three lone pairs.

Steps

Here’s how you can draw the CF4 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

In the periodic table, carbon lies in group 14, and fluorine lies in group 17.

Hence, carbon has four valence electrons and fluorine has seven valence electrons.

Since CF4 has one carbon atom and four fluorine atoms, so…

Valence electrons of one carbon atom = 4 × 1 = 4
Valence electrons of four fluorine atoms = 7 × 4 = 28

And the total valence electrons = 4 + 28 = 32

  • 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 fluorine, assume that the central atom is carbon.

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

  • And finally, draw the rough sketch
CF4 Lewis Structure (Step 1)

#2 Mark Lone Pairs

Here, we have a total of 16 electron pairs. And four C — F 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.

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 carbon, there is zero lone pair because all twelve electron pairs are over.

Mark the lone pairs on the sketch as follows:

CF4 Lewis Structure (Step 2)

#3 Mark Charges

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

Here, both carbon 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 (carbon) forms an octet. Hence, the octet rule is satisfied.

Therefore, this structure is the stable lewis structure of CF4.

Next: XeF2 Lewis Structure

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