How to draw CH2Cl2 Lewis Structure? - Science Education and Tutorials

Drawing CH2Cl2 Lewis Structure is very easy to by using the following method. Here in this post, we described step by step method to construct CH2Cl2 Lewis Structure.

Table of Contents

Key Points To Consider When Drawing The CH2Cl2 Structure

A three-step approach for drawing the CH2Cl2 Lewis structure can be used. The first step is to sketch the Lewis structure of the CH2Cl2 molecule, to add valence electron around the carbon atom; the second step is to add valence electrons to the two chlorine and two hydrogen atoms, and the final step is to combine the step1 and step2 to get the CH2Cl2 Lewis Structure.

The CH2Cl2 Lewis structure is a diagram that illustrates the number of valence electrons and bond electron pairs in the CH2Cl2 molecule. The geometry of the CH2Cl2 molecule can then be predicted using the Valence Shell Electron Pair Repulsion Theory (VSEPR Theory), which states that molecules will choose the Ch2Cl2 geometrical shape in which the electrons have from one another.

Finally, you must add their bond polarities to compute the strength of the C-Cl bond (dipole moment properties of the CH2Cl2 molecule). The carbon-chlorine bonds in dichloromethane(CH2Cl2), for example, are polarised toward the more electronegative chlorine, and because both bonds have the same size and located around four terminals with two chlorine and two hydrogen atoms, their sum is non zero due to the CH2Cl2 molecule’s bond dipole moment and the lone pairs of electron on two chlorine atoms. The CH2Cl2 molecule is classified as a polar molecule.

The molecule of dichloromethane (with tetrahedral molecular geometry) is tilted, the bond angles between chlorine, carbon, and hydrogen are 109.5 degrees. It has a difference in electronegativity values between carbon and chlorine atoms, with carbon’s pull being less than chlorine’s terminal in the CH2Cl2 molecule. As a result, it has the permanent dipole moment. The CH2Cl2 molecule has a permanent dipole moment due to an unequal charge distribution of negative and positive charges. The net dipole moment of the CH2Cl2 molecule is 1.6 D.

CH2Cl2 Lewis Structure:

The central atom is carbon, which is bordered on four terminals with two chlorine atoms, two hydrogen atoms, and no lone pair on the carbon in the tetrahedral geometry. Carbon has four outermost valence electrons, indicating that it possesses four electrons in its outermost shell, whereas chlorine only has seven valence electrons in its outermost shell. To complete the octet of the chlorine atom, a chlorine terminal atom requires one electron. If you’re interested in learning more about the chlorine octet rule, please see in our previous post.

Two Chlorine and two hydrogen atoms establish covalent connections with the central carbon atom as a result, leaving the carbon atom with no lone pair. There is no lone pair on the carbon central atom that resist the bond pairs of the two C-Cl and C-H. According to VSEPR theory, no electronic repulsion of the lone pair and bond pair leads the CH2Cl2 molecule to take on a tetrahedral molecular geometry shape.

The CH2Cl2 molecule’s C-Cl bonds are arranged in asymmetrical order around the tetrahedral molecular geometry, giving rise to the CH2Cl2 molecular shape. The CH2Cl2 molecule has a tetrahedral molecular geometry because there is no electrical repulsion between lone pair and bond pairs of CH2Cl2 molecule.

Electronegative Difference Calculation of CH2Cl2 Molecule:

The carbon atom has an electronegativity of 2.55, while chlorine has an electronegativity of 3.16 in the CH2Cl2 molecule. The difference in electronegativity can be estimated using the method below.

The electronegative value difference between carbon and chlorine
Electronegativity value of carbon = 2.55
Electronegativity value of chlorine= 3.16
Difference of electronegativity value between carbon and chlorine= 3.16 – 2.55 =0.61
Electronegativity difference between C-Cl bond calculation of CH2Cl2 molecule

The electronegative value difference between carbon and hydrogen
Electronegativity value of carbon = 2.55
Electronegativity value of hydrogen= 2.20
Difference of electronegativity value between carbon and hydrogen= 2.55 – 2.20 =0.35
Electronegativity difference between C-H bond calculation of CH2Cl2 molecule

Due to the difference in electronegativity value of greater than 0.5, the C-Cl bond of the CH2Cl2 molecule becomes polar. Because of this difference in electronegativity, the CH2Cl2 molecule’s C-Cl bond becomes polar. The electronegativity of an atom is the strength with which it may attract bound electron pairs to its side. The polarity of CH2Cl2 is discussed in our previous post.

As a result, the C-Cl bond’s dipole moment is high due to the polarization of the bonds, and all C-Cl bonds’ dipoles are arranged in the tetrahedral molecular geometry. The CH2Cl2 molecule’s total dipole moment is predicted to be 1.6 D. It has a partial negative charge for chlorine atoms and a partial positive charge for the central carbon atom.

The electron dot structure of the CH2Cl2 molecule is also known as the CH2Cl2 Lewis structure. It determines the number of outermost valence electrons as well as the electrons engaged in the CH2Cl2 molecule’s bond formation. The outermost valence electrons of the CH2Cl2 molecule must be understood while considering the Lewis structure of the molecule.

The carbon atom is the middle element in CH2Cl2 molecular geometry, with four electrons in its outermost valence electron shell, whereas the chlorine atom has seven electrons in its outermost valence electron shell.

The CH2Cl2 molecule has a total of 20 valence electrons as a result of the foregoing above said reasoning. With the core central carbon atom, the four terminal with two chlorine and two hydrogen atoms form covalent bonds, leaving the carbon atom with no lone pairs on it.

The tetrahedral molecular geometry and structure of the CH2Cl2 molecules are similar to that of the methane (CH4) molecule. Because no lone pair of a central carbon atom create interaction with C-Cl bond pairs. The bond angle of the Cl-C-H bond in the tetrahedral molecular geometry is approximately 109.5 degrees. The C-Cl and C-H bond lengths are 176 and 107 pm(picometer) respectively.

To sketch the CH2Cl2 Lewis structure by following these instructions:

Step-1: CH2Cl2 Lewis dot Structure by counting valence electron

To calculate the valence electron of each atom in CH2Cl2, look for its periodic group from the periodic table. The carbon and halogen families, which are the 14th and 17th groups in the periodic table, are both made up of carbon and chlorine atoms. In their outermost shells, carbon and chlorine have four and seven valence electrons, respectively.

Because carbon and chlorine are members of the periodic table’s carbon and halogen family groups, their valence electrons are four and seven, respectively.

Calculate the total number of valence electrons in the CH2Cl2 molecule’s outermost valence shell. The first step is to determine how many electrons are in the CH2Cl2 Lewis structure’s outermost valence shell. An electron in an atom’s outermost shell is known as a valence electron. It is represented by dots in the CH2Cl2 Lewis diagram. The CH2Cl2 molecule’s core carbon atom can be represented as follows:

Total outermost valence shell electron of carbon atom in CH2Cl2= 4
Total outermost valence shell electron of the chlorine atom in CH2Cl2= 7
The CH2Cl2 molecule has one central carbon, two hydrogen, and two chlorine atoms. Then the total outermost valence shell electrons can be calculated as follows
∴ Total outermost valence shell electrons available for CH2Cl2 Lewis structure( dot structure) = 4 +2*7+ 2*1= 20 valence electrons in CH2Cl2
calculation of total valence electron of CH2Cl2 molecule

Choose the atom with the least electronegative value atom and insert it in the center of the molecular geometry of CH2Cl2. We’ll choose the least electronegative value atom in the CH2Cl2 molecule to place in the center of the CH2Cl2 Lewis structure diagram in this phase. The electronegativity value in periodic groups grows from left to right in the periodic table and drops from top to bottom.

Step-2: Lewis Structure of CH2Cl2 for constructing around the more electronegative atom

As a result, carbon is the first atom in the periodic table’s carbon family group. Chlorine is the second member of the halogen family. The electronegative value of the carbon atom is lower than that of the chlorine atom in the CH2Cl2 molecule. Furthermore, carbon has a four electrons limit since chlorine is the most electronegative element in the CH2Cl2 molecule.

In the CH2Cl2 Lewis structure diagram, the carbon atom can be the center atom of the molecule. As a result, central carbon in the CH2Cl2 Lewis structure, with all two chlorine and two hydrogens arranged in the tetrahedral geometry.

Add valence electrons around the chlorine atom and add valence hydrogen atom, as given in the figure.

Step-3: Lewis dot Structure for CH2Cl2 generated from step-1 and step-2

Connect the exterior and core central atom of the CH2Cl2 molecule with four single bonds (two C-Cl and C-H). In this stage, use four single bonds to connect all two chlorine and two hydrogen atoms on the outside of the CH2Cl2 molecule to the central carbon atom in the middle.

Count how many electrons from the outermost valence shell have been used in the CH2Cl2 structure so far. Each C-Cl bond carries two electrons because each carbon atom is connected to two chlorine and two hydrogen atoms by two C-Cl and C-H bonds. Bond pairings of C-Cl and C-H are what they’re called.

So, out of the total of 20 valence electrons available for the CH2Cl2 Lewis structure, we used 8 for the CH2Cl2 molecule’s two C-Cl and C-H bonds. The CH2Cl2 molecule has no lone pair electron in the center of carbon. We need to put no extra electrons in the molecular geometry of CH2Cl2.

Place the valence electrons in the C-H and C-Cl bond pairs starting with the core carbon, two hydrogen, and two chlorine atoms in the CH2Cl2 molecule. In the CH2Cl2 Lewis structure diagram, we always begin by introducing valence electrons from the central carbon atom(in step1). As a result, wrap around the central carbon atom’s bond pair valence electrons first (see figure for step1).

Carbon requires 8 electrons in its outermost valence shell to complete the molecular stability, 8 electrons bond pairs in C-H and C-Cl bonds. Then place no electrons as a lone pair of electrons on the carbon atom of the CH2Cl2 molecule. Carbon already shares 8 electrons to the four single C-Cl and C-H bonds. Then place the valence electron in the chlorine atom, it placed around seven electrons(step-2). Totally, 12 valence electrons placed on the two chlorine atoms of the CH2Cl2 molecule.

We’ve positioned 8 electrons around the central carbon atom(step-3), which is represented by a dot, in the CH2Cl2 molecular structure above. The carbon atom completes its molecular stability in the CH2Cl2 molecule because it possesses 8 electrons in its bond pairs with two chlorine and two hydrogens in the outermost valence shell.

Count how many outermost valence shell electrons have been used so far using the CH2Cl2 Lewis structure. Four electron bond pairs are shown as dots in the CH2Cl2 chemical structure, whereas four single bonds each contain two electrons. The outermost valence shell electrons of the CH2Cl2 molecule are 8 +12 = 20 as a result of the calculation.

So far, we’ve used 20 of the CH2Cl2 Lewis structure’s total 20 outermost valence shell electrons. No lone pair of electrons on the carbon atom in the tetrahedral geometry of the CH2Cl2 molecule.

Complete the middle carbon atom stability and, if necessary, apply a covalent bond. The central carbon atom undergoes octet stability. Because it has a total of eight electrons in the outermost valence shell.

The core atom in the CH2Cl2 Lewis structure is carbon, which is bonded to the chlorine and hydrogen atoms by four single bonds (C-Cl and C-H). With the help of four single bonds, it already shares eight electrons. As a result, chlorine follows the octet rule and has eight electrons surrounding it on the two terminals of the CH2Cl2 molecule’s tetrahedral geometry.

How to calculate the formal charge on a carbon atom in CH2Cl2 Lewis Structure?

The formal charge on the CH2Cl2 molecule’s carbon central atom often corresponds to the actual charge on that carbon central atom. In the following computation, the formal charge will be calculated on the central carbon atom of the CH2Cl2 Lewis dot structure.

To calculate the formal charge on the central carbon atom of the CH2Cl2 molecule by using the following formula:
The formal charge on the carbon atom of CH2Cl2 molecule= (V. E(C)– L.E(C) – 1/2(B.E))
V.E (C) = Valence electron in a carbon atom of CH2Cl2molecule
L.E(C) = Lone pairs of an electron in the carbon atom of the CH2Cl2 molecule.
B.E = Bond pair electron in C atom of CH2Cl2 molecule
calculation of formal charge on carbon atom in CH2Cl2 molecule

The carbon core atom (four single bonds connected to two chlorine and two hydrogen atoms ) of the CH2Cl2 molecule has four valence electrons, no lone pair of electrons, and eight bonding electrons. Put these values for the carbon atom in the formula above.

Formal charge on carbon atom of CH2Cl2 molecule = (4- 0-(8/2)) =0

In the Lewis structure of CH2Cl2, the formal charge on the central carbon atom is zero.

Summary:

In this post, we discussed the method to construct the CH2Cl2 Lewis structure. Need to remember that, if you follow above said method, you can construct molecular dot structure very easily.