The key difference between ethanol and propanol is that the ethanol contains two carbon atoms per molecule whereas the propanol contains 3 carbon atoms per molecule.
Both ethanol and propanol are alcoholic compounds that contain a hydroxyl group (-OH) as the functional group of the molecule. Also, both are the simplest among alcohols. Since ethanol has only two carbon atoms, there is only one molecule that we can name as ethanol. However, propanol has three carbon atoms. Therefore, there can be several structures for the same molecule due to different structural and spatial arrangements of these atoms. We call these different structures as “isomers” of propanol. However, we generally refer to 1-propanol when we talk about this compound.
CONTENTS
1. Overview and Key Difference
2. What is Ethanol
3. What is Propanol
4. Side by Side Comparison – Ethanol vs Propanol in Tabular Form
5. Summary
What is Ethanol?
Ethanol is an organic compound having the chemical formula C2H5OH. We can write this formula as CH3−CH2−OH or as C2H5−OH. Either way, it represents the hydroxyl group (-OH) in the alcohol. This compound is volatile and highly flammable. Also, it is a colourless liquid with a characteristic odour. Above all, it is the major alcoholic compound that we can find in alcoholic beverages.
Figure 01: Chemical Structure of Ethanol
We can produce this compound via fermentation of sugars by yeast as a biological route. Or else, we can use petrochemical processes. Looking at its chemical properties, the molar mass of this compound is 46.07 g/mol. The melting point is around −114.14 °C, and the boiling point is around 78.24°C. Also, it is miscible with water because it can form hydrogen bonds with water molecules.
When considering the uses of ethanol, there are medical uses, recreational uses, fuel and as a solvent. It has antiseptic properties and also we can use it as an antidote. Hence, it is useful as a medicinal solvent in the pharmaceutical industry. In addition, it is a common engine fuel, and similarly, it is useful as a fuel additive.
What is Propanol?
Propanol is an organic compound having the chemical formula C3H8O. It is a colourless liquid and has a mild, alcoholic odour. Since there are three carbon atoms in propanol molecule, it has isomers. This means, these three carbon atoms can arrange in different ways to give different arrangements and structures of the same molecule. E.g., 1-propanol and 2-propanol.
Figure 02: Chemical Structure of Propanol
Furthermore, the molar mass of this compound is 60.1 g/mol. For 1-propanol, the melting point is −126 °C and the boiling point is 98 °C. Also, same as ethanol, propanol is miscible with water because it can form hydrogen bonds with the hydroxyl functional group. Thus, we can produce this compound via catalytic hydrogenation of propionaldehyde.
What is the Difference Between Ethanol and Propanol?
Ethanol is an organic compound having the chemical formula C2H5OH whereas Propanol is an organic compound having the chemical formula C3H8O. Both these are alcoholic compounds. But, one ethanol molecule contains two carbon atoms while one propanol molecule contains three carbon atoms. Therefore, this is the major difference between ethanol and propanol. Moreover, another difference between ethanol and propanol is that the ethanol has no isomers, but propanol has isomers. In overall, ethanol and propanol are two different chemical compounds having different compositions of atoms, thus different molar masses, melting points and boiling points.
The below infographic presents the difference between ethanol and propanol in tabular form.
Summary – Ethanol vs Propanol
Both ethanol and propanol are alcoholic compounds. But, the key difference between ethanol and propanol is that the ethanol contains two carbon atoms per molecule whereas the propanol contains 3 carbon atoms per molecule.
Reference:
1. “Ethanol.” Wikipedia, Wikimedia Foundation, 11 Oct. 2018. Available here
2. “1-Propanol.” Wikipedia, Wikimedia Foundation, 4 July 2018. Available here
Image Courtesy:
1.”Ethanol-structure”By Lukáš Mižoch – Own work, (Public Domain) via Commons Wikimedia
2.”Propanol flat structure”By Cacycle – Own work, (Public Domain) via Commons Wikimedia