The key difference between isopropyl alcohol and denatured alcohol is that the isopropyl alcohol has three carbon atoms whereas the denatured alcohol mainly contains ethanol, which has two carbon atoms.
Isopropyl alcohol and denatured alcohol falls under the category of alcohol since they have a –OH group. The OH group is attached to an sp3 hybridized carbon. Furthermore, these are the smaller alcohols in the series with two or three carbons. Also, both are polar liquids and have the capability to form hydrogen bonds. Therefore, both have somewhat similar physical and chemical properties. For example, both are flammable and toxic liquids.
CONTENTS
1. Overview and Key Difference
2. What is Isopropyl Alcohol
3. What is Denatured Alcohol
4. Side by Side Comparison – Isopropyl Alcohol vs Denatured Alcohol in Tabular Form
5. Summary
What is Isopropyl Alcohol?
Isopropyl alcohol, which has the IUPAC name as 2-propanol, has the same molecular formula as propanol. In fact, isopropyl alcohol is an isomer of propanol. The molecular weight of it is around 60 g mol-1. And, its molecular formula is C3H8O. The hydroxyl group of this molecule is attached to the second carbon atom in the chain. Therefore, this is a secondary alcohol.
Figure 01: Chemical Structure of Isopropyl Alcohol
Looking at its properties, the melting point of isopropyl alcohol is -88 oC, and the boiling point is 83 oC. It is miscible with water and stable under normal conditions. Also, this is a colourless, clear, flammable liquid. But, it has a strong odour. Furthermore, since this is a secondary alcohol, it undergoes all the reactions typical to a secondary alcohol. It oxidizes violently to produce acetone.
Concerning the usage, this alcohol is useful as a solvent in pharmaceuticals, household products, personal care products, and to make other chemicals.
What is Denatured Alcohol?
Denatured alcohol mainly contains ethanol. Ethanol is a simple alcohol with the molecular formula of C2H5OH. Looking at its properties, it is a clear, colourless liquid with a characteristic odour. Furthermore, it is a flammable liquid. The melting point of this compound is -114.1 oC, and the boiling point is 78.5 oC. Moreover, it is polar due to the electronegativity difference between the oxygen and hydrogen in the –OH group. Also, due to –OH group, it has the ability to form hydrogen bonds.
Figure 02: A Bottle of Denatured Alcohol
Concerning the usage, ethanol is useful as a beverage. According to the ethanol percentage, there are different types of beverages such as wine, beer, whiskey, brandy, arrack, etc. However, denatured alcohol is ethanol with other additives, which makes it unfavourable for a drink. We name it as methylated spirits because earlier, the main additive for this was methanol, which is about 10%. Other than methanol, we can add other additives such as isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, and denatonium to make denatured alcohol.
Moreover, the addition to these extra molecules doesn’t affect the chemical nature of the ethanol but makes it highly poisonous. Sometimes denatured alcohol may have a colour due to the addition of dyes. Denatured alcohol is mainly important as a solvent and a fuel. It is also useful as a cleaner, antiseptic, to preserve biological specimens, etc. Also, denatured alcohol is a cheap alternative for methanol and ethanol in various functions.
What is the Difference Between Isopropyl Alcohol and Denatured Alcohol?
Although isopropyl alcohol and denatured alcohol falls under the same category, the alcohols, there are several differences between isopropyl alcohol and denatured alcohol. The key difference between isopropyl alcohol and denatured alcohol is that the isopropyl alcohol has three carbon atoms whereas the denatured alcohol mainly contains ethanol, which has two carbon atoms. Another important difference is that the isopropyl alcohol is an individual compound while the denatured alcohol is a mixture of several compounds consisting of ethanol as the major ingredient mixed with some additives.
Summary – Isopropyl Alcohol vs Denatured Alcohol
Both isopropyl alcohol and denatured alcohol are forms of alcoholic compounds that have many important applications. The key difference between isopropyl alcohol and denatured alcohol is that isopropyl alcohol has three carbon atoms whereas denatured alcohol mainly contains ethanol, which has two carbon atoms.
Reference:
1. “Isopropyl Alcohol.” Wikipedia, Wikimedia Foundation, 25 Sept. 2018. Available here
2. “Denatured Alcohol.” Wikipedia, Wikimedia Foundation, 27 Sept. 2018. Available here
Image Courtesy:
1.”2-Propanol”By Yikrazuul – Own work, (Public Domain) via Commons Wikimedia
2.”Denaturat”By Hiuppo – Own work, (CC BY-SA 2.5) via Commons Wikimedia