Isopropyl Alcohol vs. Methanol

Attribute	Isopropyl Alcohol	Methanol
Chemical Formula	C3H8O	CH3OH
Molecular Weight	60.1 g/mol	32.04 g/mol
Boiling Point	82.6°C	64.7°C
Flash Point	11.7°C	-6.7°C
Uses	Disinfectant, solvent	Antifreeze, fuel

Introduction

Isopropyl alcohol and methanol are two common types of alcohol that are used for various purposes. While they may seem similar at first glance, they have distinct differences in terms of their properties and uses. In this article, we will compare the attributes of isopropyl alcohol and methanol to help you understand their differences.

Chemical Structure

Isopropyl alcohol, also known as isopropanol, has the chemical formula C3H8O. It is a secondary alcohol, meaning that the hydroxyl group is attached to a carbon atom that is attached to two other carbon atoms. Methanol, on the other hand, has the chemical formula CH3OH and is a primary alcohol, with the hydroxyl group attached to a carbon atom that is only attached to one other carbon atom.

Physical Properties

Isopropyl alcohol is a clear, colorless liquid with a strong odor. It has a boiling point of 82.6 degrees Celsius and a density of 0.785 g/cm3. Methanol, on the other hand, is also a clear, colorless liquid but has a slightly sweeter odor. It has a lower boiling point of 64.7 degrees Celsius and a higher density of 0.7918 g/cm3.

Flammability

Both isopropyl alcohol and methanol are flammable liquids. However, methanol is more flammable than isopropyl alcohol. Methanol has a lower flash point and autoignition temperature compared to isopropyl alcohol, making it more prone to catching fire. This difference in flammability should be taken into consideration when handling these substances.

Toxicity

One of the key differences between isopropyl alcohol and methanol is their toxicity. Isopropyl alcohol is generally considered safe for use on the skin and for disinfecting surfaces. Ingesting small amounts of isopropyl alcohol may cause mild symptoms such as nausea and dizziness. On the other hand, methanol is highly toxic and can cause severe health effects, including blindness, organ damage, and even death, if ingested or absorbed through the skin.

Uses

Isopropyl alcohol is commonly used as a disinfectant, solvent, and cleaning agent. It is found in many household products such as rubbing alcohol, hand sanitizers, and surface cleaners. Isopropyl alcohol is also used in the pharmaceutical and cosmetic industries. Methanol, on the other hand, is primarily used as an industrial solvent, fuel additive, and antifreeze. It is also used in the production of formaldehyde and other chemicals.

Conclusion

In conclusion, while isopropyl alcohol and methanol are both types of alcohol, they have distinct differences in terms of their chemical structure, physical properties, flammability, toxicity, and uses. Isopropyl alcohol is generally safer and more commonly used for disinfection and cleaning purposes, while methanol is more toxic and primarily used in industrial applications. It is important to understand these differences when choosing between the two substances for a specific application.