Is CH2Cl2 Polar: Insights and 5 Facts You Must Know

Is ch2cl2 polar or is it non-nonpolar and whether it is ionic or covalent all these facts and characteristics have been discussed in detail in this article.

We know ch2cl2 is a tetrahedral molecule and not all tetrahedral molecules are polar. But ch2cl2 is a polar molecule and almost all the tetrahedral molecules have a bond angle of 109.5 degrees. All the detailed facts we shall see in the later sections.

Why is ch2cl2 polar?

In simple words, a polar molecule means that one end of the molecule will have a positive charge and the other end will have a negative charge this leads to the formation of a dipole and makes a molecule polar.

Talking about the polarity of Ch2Cl2, yes it is a polar molecule. The important factors that govern the polarity of Ch2Cl2 are shape, dipole moment, and its electronegativity. As these factors help us in determining and understanding the polarity concept of Ch2Cl2, how and why all the reasons and facts have been discussed in the section below.

Ch2Cl2 is also known as dichloromethane (or we can also say methylene chloride). It is an organic compound (molecule). In appearance, it is a liquid (colorless) and its odor is somewhat like chloroform (faint). Its observed density is 1.326 g/cm³ (at a temperature of 20 degrees Celsius) and boils at a temperature of 39.6 degrees Celsius. It is seen to be miscible in alcohol, carbon tetrachloride, benzene, etc.

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Coming to its occurrence part, it is found / source in volcanoes, ocean, wetlands, etc. (these are the natural sources of Ch2Cl2). And it is formed in the environment as a result of the emission of industries. We can also prepare it by the reaction of methane (or chloromethane) with chlorine (gas) at a temperature between 410-510 degrees Celsius. Another method of preparation is by reducing chloroform (in presence of Zinc and hydrochloric acid).

Is CH2Cl2 Polar: Insights and 5 Facts You Must Know 1

Now let’s look at the shape (factor). As we know the shape of a molecule influences polarity of that particular molecule, meaning it plays a very important role in determining polarity. The dipole (net) moment is as a result of the unequal distribution of the electron between the atoms. So there are unequal charges, so they cannot cancel each other and causes the molecule to be polar.

The shape of the Ch2Cl2 molecule is tetrahedral, so it is an unsymmetrical molecule and there is no scope for charges to cancel out. So most of the time a polar molecule will be an asymmetrical molecule we can now say it is a polar molecule.

The next factor is electronegativity. So now we are going to analyse how or what role the concept of electronegativity plays a role in determining the polarity of a molecule. Consider two atoms having the same electronegativity meaning the electron density distribution will be equal. But if the atoms have different electronegativities ( there should be some difference in their electronegativities ) what will happen is the atom among the two having greater/more electronegativity will tend to pull electron density towards itself.

This will create a negative polarity on that side and the other side of the bond will be left with positive electronegativity. So more/greater difference in electronegativity make/increases the polarity, provided the difference should not exceed 1.7 for a covalent bond because beyond that difference a bond is ionic. Hence electronegativity plays important role in increasing the polarity.

Now, let’s have a look at the electronegativities of Ch2Cl2. The electronegativity of the hydrogen is observed to be 2.2, carbon is 2.5 and the chlorine atom has about 3.1. So the difference in their electronegativities is 0.3 for C-H and 0.6 for C-Cl. Hence it confirms that dichloromethane is a polar molecule.

Now, coming to the next factor i.e. dipole moment. The criteria for dipole moment is there should be some amount of difference in the electronegativity of atoms that we are considering. More the difference in electronegativity more will be the dipole moment.

In the earlier section, we have seen the difference in electronegativity of C-H is 0.3 and that of C-Cl is 0.6. So, yes it leads to a dipole moment and the molecule of Ch2Cl2 becomes polar.

Is ch2cl2 polar covalent?

So a covalent bond is formed by sharing of electrons. Similar is the case with Ch2Cl2, the bond formed is covalent. And in the earlier section, we have in detail that Ch2Cl2 is polar. Now let’s understand how it is covalent.

Here electronegativity of the molecule will help us determine whether it is covalent or not. If the difference in electronegativity is more than 1.7 a compound or molecule is ionic but if it is less than that it is a covalent compound.

We have seen the difference in electronegativity of Ch2Cl2 does not exceed 1.7 it is less than that (0.3 and o.6 for C-H and C-Cl respectively). Hence we can say Ch2Cl2 is covalent. Yes, Ch2Cl2 is a polar covalent compound.

Is ch2cl2 polar or nonpolar covalent bond?

Ch2Cl2 is a polar covalent bond. Its shape is tetrahedral (asymmetrical), electronegativity difference is not equal (there is a difference of 0.3 and 0.6 for C-H and C-Cl respectively) and there exists a dipole moment. The three factors shape, electronegativity, and dipole moment confirm that Ch2Cl2 is polar.

The bond of Ch2Cl2 is formed covalently. The electronegativity difference does not exceed 1.7 this confirms that it is a covalent bond. Hence we can say Ch2Cl2 is a polar covalent bond.

Is ch2cl polar aprotic?

To understand whether ch2Cl2 is polar protic or aprotic we need to understand this concept in general. A solvent is said to be a polar protic solvent if it has one hydrogen (at least) atom that is linked/connected (directly) to atoms such as OH or NH bond (electronegative atoms ).

For polar aprotic solvents atom of hydrogen is not directly connected to OH or NH (electronegative atoms ) meaning not capable of forming a hydrogen bond. Some common examples of polar aprotic solvents are acetone, DMF, HMF, etc.

Now coming to the structure of ch2Cl2 can we see any link of a hydrogen atom to an electronegative atom such as OH or NH? No there is no such linkage in it. Hence it is not capable of forming a hydrogen bond. So we can say Ch2Cl2 is polar aprotic.

Is ch2cl2 more polar than chcl3?

As we know electronegativity plays a very important role in determining polarity along with dipole moment and shape. The shape of both Ch2Cl2 and ChCl3 is tetrahedral so we cannot use the factor (shape ) to determine the extent of more polarity in this case.

But it has been observed that the electronegativity is more in Ch2Cl2 than ChCl3. Next coming to the dipole moment, the dipole moment in Ch2Cl2 is observed to be 1.6 debye and that of CHCl3 is 1.01 debye. The more the dipole moment, the more polar will be the molecule.

We can see clearly that the dipole moment of dichloromethane is more than that of ChCl3. Hence it is now confirmed Ch2Cl2 is more polar than CHCl3.

Is ch2cl2 soluble in water?

We know water is a polar solvent and polar-polar molecules are well miscible. Yes, Ch2Cl2 is soluble in water but moderately 2g/100 mL at a temperature of 20 degrees Celsius. But Ch2Cl2 is better miscible in organic solvents (alcohols, benzene, etc.).

Solubility of a molecule differs in air and liquids at different temperatures, so the solubility of ch2cl2 will also be different in various mediums at different temperatures .

Is ch2cl2 protic?

No, Ch2Cl2 cannot be protic as for a solvent to be protic it should have (at least) one hydrogen linked to electronegative atoms( OH or NH ) and be able to form a hydrogen bond . This is not the case with Ch2Cl2 as it does not have any hydrogen and electronegative atom linkage and hence no hydrogen bonding. Therefore Ch2Cl2 is protic.

As we know ch2cl2 is a tetrahedral molecule and is asymmetrical, so it is a polar aprotic solvent with a dipole moment of 1.6 debye.

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Sania Jakati

This is Sania Jakati from Goa. I am an aspiring chemist pursuing my post graduation in organic chemistry. I believe education is the key element that moulds you into a great human being both mentally and physically. I’m glad to be a member of scintillating branch of chemistry and will try my best to contribute whatever I can from my side and Lambdageeks is the best platform where I can share as well as gain knowledge at the same time.