Ready to learn how to draw the lewis structure of CH2?
Here, I have explained 5 simple steps to draw the lewis dot structure of CH2 (along with images).
So, if you are ready to go with these 5 simple steps, then let’s dive right into it!
Lewis structure of CH2 contains two single bonds between the Carbon (C) atom and each Hydrogen (H) atom. The Carbon atom (C) is at the center and it is surrounded by 2 Hydrogen atoms (H). The Carbon atom has 2 lone pairs.
Let’s draw and understand this lewis dot structure step by step.
(Note: Take a pen and paper with you and try to draw this lewis structure along with me. I am sure you will definitely learn how to draw lewis structure of C2H2).
5 Steps to Draw the Lewis Structure of C2H2
Step #1: Calculate the total number of valence electrons
Here, the given molecule is CH2. In order to draw the lewis structure of CH2, first of all you have to find the total number of valence electrons present in the CH2 molecule.
(Valence electrons are the number of electrons present in the outermost shell of an atom).
So, let’s calculate this first.
Calculation of valence electrons in CH2
- For Carbon:
Carbon is a group 14 element on the periodic table. 
Hence, the valence electrons present in carbon is 4 (see below image).
- For Hydrogen:
Hydrogen is a group 1 element on the periodic table. 
Hence, the valence electron present in hydrogen is 1 (see below image).
Hence in a CH2 molecule,
Valence electrons given by Carbon (C) atom = 6
Valence electrons given by each Hydrogen (H) atom = 1
So, total number of Valence electrons in CH2 molecule = 6 + 1(2) = 8
Step #2: Select the center atom (H is always outside)
While selecting the atom, always put the least electronegative atom at the center.
(Remember: Fluorine is the most electronegative element on the periodic table and the electronegativity decreases as we move right to left in the periodic table as well as top to bottom in the periodic table). 
Here in the CH2 molecule, if we compare the carbon atom (C) and hydrogen atom (H), then hydrogen is less electronegative than carbon. But as per the rule, we have to keep hydrogen outside.
So, carbon should be placed in the center and the remaining 2 hydrogen atoms will surround it.
Step #3: Put two electrons between the atoms to represent a chemical bond
Now in the above sketch of CH2 molecule, put the two electrons (i.e electron pair) between each carbon atom and hydrogen atom to represent a chemical bond between them.
These pairs of electrons present between the Carbon (C) and Hydrogen (H) atoms form a chemical bond, which bonds the carbon and hydrogen atoms with each other in a CH2 molecule.
Step #4: Complete the octet (or duplet) on outside atoms. If the valence electrons are left, then put the valence electrons pair on the central atom
Don’t worry, I’ll explain!
In the Lewis structure of CH2, the outer atoms are hydrogen atoms.
So now, you have to check whether these hydrogen atoms are forming a duplet or not! (because hydrogen requires only 2 electrons to have a complete outer shell).
You can see in the above image that both the hydrogen atoms form a duplet.
Also, only 4 valence electrons of CH2 are used in the above structure.
But there are total 6 valence electrons in CH2 molecule (as calculated in step #1).
So the number of electrons left to be kept on the central atom = 6 – 4 = 2.
So let’s keep these two electrons (i.e 1 electron pairs) on the central atom.
Now, let’s move to the next step.
Step #5: Check the stability of lewis structure by calculating the formal charge on each atom
Now, you have come to the final step and here you have to check the formal charge on carbon atom (C) as well as each hydrogen atom (H).
For that, you need to remember the formula of formal charge;
Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2
- For Carbon:
Valence electrons = 4 (as it is in group 14)
Nonbonding electrons = 2
Bonding electrons = 4
- For Hydrogen:
Valence electron = 1 (as it is in group 1)
Nonbonding electrons = 0
Bonding electrons = 2
|Formal charge||=||Valence electrons||–||Nonbonding electrons||–||(Bonding electrons)/2|
So you can see above that the formal charges on carbon as well as hydrogen are “zero”.
Hence, there will not be any change in the above structure and the above lewis structure of CH2 is the final stable structure only.
Each electron pair (:) in the lewis dot structure of CH2 represents the single bond ( | ). So the above lewis dot structure of CH2 can also be represented as shown below.
Related lewis structures for your practice:
Lewis Structure of HO2-
Lewis Structure of C2HCl
Lewis Structure of S2O
Lewis Structure of BrCl3
Lewis Structure of NO2Cl