Ethanol is a chemical compound having the chemical formula C2H5OH. It is a well-known substance that is mainly consumed in the form of alcohol. In the pure state, It is a colorless liquid that has a characteristic odor. Many of you may have doubts regarding whether ethanol is polar or not. In this article, we will discuss the same and will also cover the properties and its applications.
So, Is Ethanol Polar or Nonpolar? Ethanol is polar in nature because of the presence of the hydroxyl group(-OH) attached to the carbon end. Due to the difference between the electronegativity of oxygen and the hydrogen atom, the hydroxyl group becomes polar. As a result, the molecule of ethanol gives non zero dipole moment and becomes a polar molecule.
Ethanol is a well-known substance that is majorly consumed by humans all over the world in the form of alcohol.
In the pure state, it is colorless in appearance with a characteristic smell. It is volatile and flammable in nature.
This substance is produced by the process of fermentation of sugary fruits by yeast.
If we talk about the chemical composition of ethanol, it is composed of 2 carbon atoms, 6 hydrogen atoms, and 1 oxygen atom.
The hydroxyl group is attached to one end of the carbon chain. The alcohol compounds have a hydroxyl group attached.
The general formula of alcohol is R-OH. where R is the series of hydrocarbon and -Oh is the hydroxyl group.
The molecular mass of ethanol is around 46.069 g·mol−1. It is calculated as below
Mol mass of Ethanol = 2 * 12 (Mol mass of C) + 6 * 1 (Mol mass of H) + 1 * 16 (Mol mass of oxygen) = 46.069 g·mol−1.
The Hydroxyl group attached is polar in nature due to the difference between the electronegativity of oxygen and hydrogen atoms.
The electronegativity of Oxygen is 3.44 and that of hydrogen is 2.2. Being more electronegative, Oxygen atom attracts the bonded pair electron towards its side and gains a partial negative charge.
And the hydrogen atom gains a relatively negative charge on it.
What are Polar and Nonpolar Molecules?
The molecules are formed by the interatomic forces like hydrogen bonds, metallic bonds, covalent, and ionic.
Ionic and covalent bonds are the strongest bonds among the above bonds.
Polar Molecules: Polar molecules have two poles (positive and negative) generated across it. These molecules have unequal distribution of charge over the atoms involved in it.
The atoms forming a polar covalent bond always differ in their electronegativity because it is the strength of an atom to attract the bonded electron pair towards it.
As a result, the higher electronegative atom gains a partial negative charge and other atom gains partial positive charge.
Some of the examples of polar molecules are SCl2, OF2, etc. You can check out the reason for the polarity of SCl2.
Nonpolar Molecules: These types of molecules do not have any poles generated in them. The dipole moment of such molecules comes out to be 0.
The atoms that have the same electronegativity form nonpolar bonds because both atoms have an equal influence on the bonded charge.
Some of the examples of such molecules are Hexane, Br2, etc. You can check the reason for the non-polarity of Br2.
Why is Ethanol a Polar Molecule?
Ethanol is the type of alcohol having a carbon chain of 2 carbon atoms associated with 1 hydroxyl group.
The hydroxyl group connected with the carbon end generates the polarity in the entire molecule.
This is because of the difference between the electronegativity of oxygen and hydrogen atoms.
The difference between the electronegativity of oxygen (3.44) and that of hydrogen (2.2) is around 1.24 units.
Due to this difference, the molecule of ethanol ensures the polarity across it.
If we talk about the geometrical shape of ethanol, the carbon has a tetrahedral shape. While the oxygen forms bent shape.
Factors affecting the polarity of a molecule
To check whether a molecule is polar or not, we need to know some of the below parameters.
Electronegativity: the term electronegativity of an atom is the strength of an atom to attract the bonded electron pairs towards it.
If there is a difference between the electronegativity between two atoms forming a molecule, then there exists polarity across the bond.
It means the charge distribution across the bond is non-uniform ie; unevenly distributed.
The polarity of a molecule is directly proportional to the difference between the electronegativity of atoms.
Dipole Moment: The value of the dipole moment of a molecule is the measure of its polarity. Greater the value of the dipole of a molecule more is its polarity.
The dipole moment of a molecule is the product of the charge on atoms and the distance between them.
It is denoted by D. Its SI unit is Debye.
Geometrical Structure: The geometrical structure of a molecule is a physical parameter that helps in checking whether a molecule is polar or not.
It is generally observed that asymmetrically shaped molecules are polar in nature because their dipoles do not cancel each other and result in a non zero dipole moment.
Whereas the symmetrically shaped molecules tend to be non-polar in nature.
Below is the image of the molecular structure of ethanol
Properties of Ethanol
- Ethanol or Ethyl Alcohol is a colorless liquid at standard conditions of temperature and pressure.
- It is flammable and volatile in nature
- It has a very low melting point of around -114.5° C or −173.45° F and its boiling point is 78.24 °C or 172.83 °F.
- The molecular mass of ethanol is 46.069 g·mol−1.
- The density of ethanol is 789 g/l that is around 20% less than that of water.
- Being a polar substance, it is a very good solvent itself.
- It is completely soluble in water.
- Baing a covalent compound, It does not conduct electricity because of the absence of free ions.
Uses of Ethanol
- Ethanol is commonly used as alcohol consumed by humans majorly across the globe.
- It is widely used in the sanitizer as a disinfectant for killing viruses and bacterias.
- It is also added in the fuel to avoid the knocking effect in engines of automobiles.
- It has great use in the cosmetic industry. It is a common ingredient in perfumes, lotions, etc.
- It is also added in paints as a preservative due to its effective solvent property.
- It is also used for the manufacturing of cleansing product chemicals.
Ethanol is a type of alcohol having two carbon atom chains having a hydroxyl group attached at one end.
Due to the difference between the electronegativity of oxygen and the hydrogen atom, the hydroxyl (-OH) group is polar.
As a result, the entire molecule is polar and results in a non zero dipole moment.
Due to these reasons, ethanol is a polar substance.
Guys, if you have any questions regarding the polarity of ethanol, you can ask them in the comment section. We will reach out to you as soon as possible.