The Lewis structure of CH2Cl2 contains four single bonds, with carbon in the center, and two hydrogens and two chlorines on either side. There are three lone pairs on each chlorine atom, and carbon atom and hydrogen atom do not have any lone pair.
Steps
By using the following steps, you can easily draw the Lewis structure of CH2Cl2:
#1 Draw skeleton
#2 Show chemical bond
#3 Mark lone pairs
#4 Calculate formal charge and check stability (if octet is already completed on central atom)
Let’s one by one discuss each step in detail.
#1 Draw skeleton
In this step, first calculate the total number of valence electrons. And then, decide the central atom.
- Let’s calculate the total number of valence electrons
We know that… carbon is a group 14 element, hydrogen is a group 1 element, and chlorine is a group 17 element. Hence, carbon has four valence electrons, hydrogen has one valence electron, and chlorine has seven valence electrons.
Now CH2Cl2 has one carbon atom, two hydrogen atoms, and two chlorine atoms.
So the total number of valence electrons = valence electrons of carbon atom + (valence electrons of hydrogen atom × 2) + (valence electrons of chlorine atom × 2)
Therefore, the total number of valence electrons = 4 + 2 + 14 = 20
- Now decide the central atom
We can not assume hydrogen as the central atom, because the central atom is bonded with at least two other atoms. And hydrogen has only one electron in its last shell, so it can not make more than one bond.
Therefore, choose the central atom from carbon and chlorine.
The atom with the least electronegative value is placed at the center. By looking at the periodic table, we get the electronegativity values for carbon and chlorine as follows:
Electronegativity value of carbon = 2.55
Electronegativity value of chlorine = 3.16
Obviously, carbon is less electronegative than chlorine. Hence, assume that carbon is the central atom.
So now, put carbon in the center and hydrogens and chlorines on either side. And draw the rough skeleton structure for the Lewis structure of CH2Cl2 something like this:
Also read: How to draw Lewis structure of PCl5 (4 steps)
#2 Show chemical bond
Place two electrons between the atoms to show a chemical bond. Since carbon is surrounded by hydrogens and chlorines, use eight electrons to show four chemical bonds as follows:
Also read: How to draw Lewis structure of C2H6 (3 steps)
#3 Mark lone pairs
As calculated earlier, we have a total of 20 valence electrons. And in the above structure, we have already used eight valence electrons. Hence, twelve valence electrons are remaining.
Two valence electrons represent one lone pair. So twelve valence electrons = six lone pairs.
Note that carbon is a period 2 element, so it can not keep more than 8 electrons in its last shell. Hydrogen is a period 1 element, so it can not keep more than 2 electrons in its last shell. And chlorine is a period 3 element, so it can keep more than 8 electrons in its last shell.
Also, make sure that you start marking these lone pairs on outside atoms first. And then, on the central atom.
The outside atoms are hydrogens and chlorines. But hydrogen can not keep more than 2 electrons in its last shell. Hence, don’t mark the lone pairs on hydrogen.
So each chlorine will get three lone pairs. And the central atom (carbon) will not get any lone pair, because all six lone pairs are used.
Now draw the Lewis structure of CH2Cl2 something like this:
In the above structure, you can see that the octet is completed on the central atom (carbon), and also on the outside atoms. Therefore, the octet rule is satisfied.
After completing the octet, one last thing we need to do is, calculate the formal charge and check the stability of the above structure.
Also read: How to draw Lewis structure of CHCl3 (4 steps)
#4 Calculate formal charge and check stability
The following formula is used to calculate the formal charges on atoms:
Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons
Collect the data from the above structure and then, write it down below as follows:
- For carbon atom
Valence electrons = 4
Nonbonding electrons = 0
Bonding electrons = 8
Formal charge = 4 – 0 – ½ (8) = 0
- For each hydrogen atom
Valence electrons = 1
Nonbonding electrons = 0
Bonding electrons = 2
Formal charge = 1 – 0 – ½ (2) = 0
- For each chlorine atom
Valence electrons = 7
Nonbonding electrons = 6
Bonding electrons = 2
Formal charge = 7 – 6 – ½ (2) = 0
Mention the formal charges of atoms on the structure. So the Lewis structure of CH2Cl2 looks something like this:
In the above structure, you can see that the formal charges of all atoms are zero. Therefore, this is the stable Lewis structure of CH2Cl2.
And each horizontal line drawn in the above structure represents a pair of bonding valence electrons.
Related
- Lewis structure of PCl5
- Lewis structure of C2H6
- Lewis structure of CHCl3
- Lewis structure of H2
- Lewis structure of SF2
External video
- CH2Cl2 Lewis Structure: How to Draw the Lewis Structure for CH2Cl2 (Dichloromethane) – Wayne Breslyn
External links
- CH2Cl2 Lewis structure, Molecular geometry, Hybridization, Bond angle – Topblogtenz
- CH2Cl2 lewis structure, molecular geometry, polarity – Geometry of Molecules
- Dichloromethane (CH2Cl2) Lewis Structure – Chemistry School
- Chemical Bonding: CH2Cl2 Lewis Structure – The Geoexchange
- CH2Cl2 Lewis Structure, Molecular Geometry, Hybridization, and MO Diagram – Techiescientist
- Draw the Lewis structure for CH2Cl2 and state its molecular geometry. Is it polar or nonpolar? – Homework.Study.com
- CH2Cl2 Lewis Structure, Geometry – Kemicalinfo
- There are 3 acceptable Lewis structures for CH2Cl2. What are the 3 Lewis structures? – Quora
- Lewis Structure of CH2Cl2 – Laurence Lavelle
- CH2Cl2 Lewis Structure in 6 Steps (With Images) – Pediabay
- CH2Cl2 Lewis Structure (Dichloromethane) – Pinterest
- How to draw CH2Cl2 Lewis Structure? – Science Education and Tutorials
- CH2Cl2 Geometry and Hybridization – Chemistry Steps
- Write the Lewis structure for CH2Cl2 – Studocu
- How many electrons are shared in the Lewis structure of CH2Cl2? – Brainly
- Draw the Lewis structure of CH2Cl2 – Numerade
- How many electrons are shared in the Lewis structure of CH2Cl2? – Socratic
- CH2Cl2 Lewis Structure Electron geometry Valence electrons Molecular geometry – Bartleby
Deep
Rootmemory.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.