Difference Between Ethanol and Isopropanol

Key Difference – Ethanol vs Isopropanol
 

Both ethanol and isopropanol are organic compounds known as alcohols. The key difference between ethanol and isopropanol is that ethanol has a linear molecular structure whereas isopropanol has a branched molecular structure.

Both ethanol and isopropanol contain –OH (hydroxyl) groups as their functional group. Ethanol is also called ethyl alcohol. Another name for isopropanol is 2-propanol.

CONTENTS

1. Overview and Key Difference
2. What is Ethanol
3. What is Isopropanol
4. Side by Side Comparison – Ethanol vs Isopropanol in Tabular Form
5. Summary

What is Ethanol?

Ethanol is an alcohol having the chemical formula C₂H₅OH. Ethanol has many uses including the application as a fuel, as an ingredient in food and beverages industry, etc. Ethanol is a flammable, volatile liquid with a characteristic odour and a sweet taste. Ethanol contains an ethyl group bonded to a hydroxyl group.

The molar mass of ethanol is 46 g/mol. Due to the presence of –OH groups, ethanol molecules can form hydrogen bonds with other hydrogen bond forming molecules. Due to the difference between the electronegativity values of the oxygen atom and carbon atom, the ethanol molecule is a polar molecule. Therefore, ethanol is a proper solvent for polar compounds.

Ethanol is produced via two methods;

1. Industrial production via ethylene hydration
2. Biological production via fermentation.

Ethanol is the main ingredient in the production of some alcoholic beverages. And also, it is used as a solvent for paints. Above all, ethanol is a fuel. And also, it is a useful intermediate in the synthesis of different chemical compounds such as ethanoic acid, polymers, esters, etc.

What is Isopropanol?

Isopropanol is an alcohol having the chemical formula C₃H₈O. The IUPAC name of this compound is 2-propanol. It is a flammable liquid that is colourless and has a strong odour. This compound has an isopropyl group (a branched alkyl group) bonded to a hydroxyl group (-OH).  This alcohol is categorized as secondary alcohol because there are two more carbon atoms attached to the carbon atom that is bonded to the –OH group.

The molar mass of isopropanol is 60 g/mol. The melting point is -88°C and the boiling point is 108°C. This compound is an isomer of 1-propanol.

There are three main ways of producing isopropanol;

1. Direct Hydration

In the direct hydration method, propene and water react with each other. The reaction can be carried out in either the liquid phase or in the gas phase. The production is done under high pressures and in the presence of an acidic catalyst.

2. Indirect Hydration

Indirect hydration includes the reaction between propene and sulfuric acid, which gives a mixture of sulfate esters.

3. Hydrogenation of Acetone

The hydrogenation of acetone gives isopropyl alcohol in the process of Raney nickel catalyst.

There are various uses of isopropyl alcohol; used as a solvent for nonpolar compounds because isopropyl alcohol is moderately polar. And also it evaporates quickly. Thus, it is suitable as a solvent. Apart from that, there are medical applications of isopropyl alcohol such as the production of rubbing alcohol, hand sanitizers, etc. in the laboratory; it is used as a preservative for specimens.

What is the Difference Between Ethanol and Isopropanol?

Summary – Ethanol vs Isopropanol

Ethanol and isopropanol are alcohol compounds. These compounds contain hydroxyl groups (-OH) as their functional group. The difference between ethanol and isopropanol is that ethanol has a linear molecular structure whereas isopropanol has a branched molecular structure.

Reference:

1. “Isopropyl Alcohol.” Wikipedia, Wikimedia Foundation, 31 Mar. 2018. Available here 
2. “Isopropyl Alcohol.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine. Available here  

Image Courtesy:

1.’2-Propanol’By Yikrazuul – Own work, (Public Domain) via Commons Wikimedia 
2.’Ethanol-2D-skeletal’By Bryan Derksen – Own work, (Public Domain) via Commons Wikimedia