No, Diethyl Ether is not polar.
This article will explain.
Is Diethyl Ether Polar or Non-Polar? (Explained)
Diethyl ether is regarded as a non-polar solvent because of its lower dielectric constant (4.33).
However, by definition, most organic molecules (including ethers) are polar since they have a dipole moment.
The term “polar”, in the context of solvents, indicates solvents having a higher polarity, and “non-polar” refers to solvents having a lower polarity. But this is relative.
On the polarity scale, diethyl ether is present at the lower end and hence, is considered as a non-polar substance.
In the article that follows, you’ll learn more about Diethyl Ether and its polar qualities.
General Properties of Diethyl Ether
|Molecular Weight or Molar Mass||74.12 g/mol|
|Melting Point of Diethyl Ether||-116.3 °C|
|Boiling Point of Diethyl Ether||34.6 °C|
What is Diethyl Ether?
Also called ether and ethoxyethane (IUPAC name), diethyl ether has a low boiling point and a distinctive smell, and it is colorless, odorless, and extremely flammable.
It is the most common chemical compound in the class of ethers.
It is the isomer of butanol.
The formula for diethyl ether is CH3-CH2-O-CH2-CH3.
It is commonly used as a solvent and a general anesthetic.
Diethyl ether is sparingly soluble in water with a solubility of 6.9 g/100 mL.
Due to its high flammability and volatility, it should not be used near open flames or electrically heated devices.
Synthesis of Diethyl Ether
Sulphuric acid is used to dehydrate ethanol to produce ether.
The chemical reaction is given as follows.
2CH3CH2OH + 2H2SO4 → (CH3CH2)2O + H2SO4 + H2O
Physical Properties of Diethyl Ether
|Odor||A sweet, pungent odor|
|Vapour Pressure||439.8 mm Hg at 20 °C|
|Solubility||Due to their polar nature, ethers are more soluble in water than alkanes.|
Chemical Properties of Diethyl Ether
As a highly flammable substance, ether undergoes combustion reactions that produce carbon dioxide and water.
C2H5OC2H5 + 6O2 → 4CO2 + 5H2O
The halogens such as chlorine and bromine react with ether to form a halo substituted ether, which then undergoes a substitution reaction in the absence of sunlight.
Uses of Diethyl Ether
- It is commonly used as a laboratory solvent.
- It is used as a solvent for alkaloids, oils, resins, fats, dyes, and waxes.
- In cellulose acetate and the plastic industry, it is used to recover acetic acid from aqueous solutions.
What is the Polarity of a Substance?
Polarity refers to “a state or a condition of an atom or molecule being charged both positively and negatively, particularly in the case of magnetic poles or electric poles.”
To put it simply, polarity refers to the physical properties of compounds such as their boiling point, melting point, and solubility.
A bond’s polarity is a result of interactions between molecules and atoms with different electronegativities.
Polarity Of Molecules
A bond’s or a molecule’s polarity is determined by the electronegativity of the atoms or molecules.
There are mainly three types of molecules: polar molecules, non-polar molecules, and ionic molecules.
But we will be discussing polar and non-polar molecules.
When a molecule is said to have more positive charges on one end, and negative charges on the other, creating an electrical pole, it is said to be a polar molecule.
A molecule with a polar bond will have a center of negative charge on one side and a center of positive charge on the opposite side.
The whole molecule will be polar.
The non-polar molecules are those molecules lacking charge at the end due to the finely distributed electrons and those molecules which symmetrically cancel each other out.
A polar molecule cannot mix with a non-polar molecule in a solution.
For instance, water and oil cannot mix.
Water is polar in this solution, whereas oil is nonpolar.
As these two molecules cannot be mixed, they do not form a solution.
Examples of Polar and Non-polar Molecules
A molecule can either be polar or non-polar.
The atoms of a non-polar molecule are arranged in a way that their electronegativity is canceled by the orbital electrons in the outer region.
- Pyramidal and V-shaped molecules are generally considered polar. Linear molecules, on the other hand, are nonpolar molecules.
- Due to the difference in electronegativities between oxygen and hydrogen, water is said to be a polar molecule. When compared to hydrogen, oxygen is a highly electronegative atom.
- Nonpolar molecules, such as fats, oil, petrol, and gasoline, do not dissolve in water, as nonpolar means insoluble in water.
- Based on how its oxygen and hydrogen atoms are arranged, glucose is another example of a polar molecule.
Why is Diethyl Ether Non-polar?
The oxygen atom in ethers is surrounded by an alkyl group, making them rather nonpolar.
Since alkyl groups surround it, the oxygen atom is largely prevented from participating in hydrogen bonding.
Thus, ethers have a lower boiling point than alcohols of similar molecular weights.
However, as ether’s alkyl chains become longer, the difference in boiling points gets smaller.
This is because of the increased Van der Waals forces as the number of carbon atoms increases, and hence, there is an increase in the number of electrons as well.
The two lone pairs of electrons on the oxygen atoms allow ethers to form hydrogen bonds with water.
Compared with alkenes, ethers have a greater degree of polarity, but are not as polar as alcohols, esters, or amides of similar structures.
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