Difference Between Acetaldehyde and Acetone

Main Difference – Acetaldehyde vs Acetone

Acetaldehyde and acetone are organic compounds composed of carbon atoms, one oxygen atom along with some hydrogen atoms. But they have different chemical and physical properties because they have different functional groups. A functional group is a portion of atoms and is a group of atoms that determines the properties of the molecule. Both acetaldehyde and acetone are liquid compounds at room temperature and pressure. The main difference between acetaldehyde and acetone is that acetaldehyde is an aldehyde whereas acetone is a ketone.

Key Areas Covered

1. What is Acetaldehyde
     – Definition, Chemical Properties, Uses
2. What is Acetone
     – Definition, Chemical Properties
3. What is the Difference Between Acetaldehyde and Acetone
     – Comparison of Key Differences

Key Terms: Acetaldehyde, Acetone, Aldehyde, Functional Group, Ketone

Difference Between Acetaldehyde and Acetone - Comparison Summary

What is Acetaldehyde

Acetaldehyde is an organic compound having the chemical formula C2H4O. This compound exists as a colorless liquid at room temperature and pressure. It is an aldehyde composed of an aldehyde group (-CHO). The molar mass of acetaldehyde is 44.05 g/mol.

Main Difference - Acetaldehyde vs Acetone

Figure 1: Chemical Structure of Acetaldehyde

It is a simple aldehyde molecule having a methyl group attached to an aldehyde group. The melting point of acetaldehyde is −123.37 °C and the boiling point is 20.2 °C. The systematic IUPAC name for acetaldehyde is ethanal. Acetaldehyde is used in the production of some chemical compounds such as 1-butanol, ethyl acetate, etc. It is also used in the production of perfumes, synthetic rubber, flavorings, etc. Pure acetaldehyde is a colorless, flammable liquid.

The major process of acetaldehyde production is called Wacker process. It includes the catalysis of the oxidation of ethylene to acetaldehyde. The catalyst is a mixture of two components: palladium chloride and copper chloride.

Acetaldehyde undergoes some important chemical reactions such as condensation reactions, tautomerization, etc. However, it is recognized as a carcinogenic compound for humans. It is toxic when exposed for a long period. It is an irritant for skin and eyes.

What is Acetone

Acetone is an organic compound having the chemical formula C3H6O. The molar mass of this compound is 58.08 g/mol. It is a ketone. At room temperature and pressure, it is a colorless, volatile and flammable liquid. It is the simplest ketone among ketone compounds. It has a pungent odor.

Difference Between Acetaldehyde and Acetone

Figure 2: Chemical Structure of Acetone

The IUPAC name for acetone is Propan-2-one. The melting point is −94.7 °C and boiling point is 56.05 °C. It is miscible with water. Acetone can be produced directly or indirectly from propylene. The modern method is cumene process. Here, benzene is alkylated with propylene to produce the compound cumene. Then this cumene is oxidized by air. This gives phenol and acetone. Therefore, acetone is produced along with phenol.

Acetone is mainly used as a solvent; it is also used as an antiseptic. It can be found in plants, vehicle exhaust, as a product of animal fat metabolism. Acetone is less dense than water and the acetone vapor is heavier than normal air.

Difference Between Acetaldehyde and Acetone

Definition

Acetaldehyde: Acetaldehyde is an organic compound having the chemical formula C2H4O.

Acetone: Acetone is an organic compound having the chemical formula C3H6O.

Category

Acetaldehyde: Acetaldehyde is an aldehyde.

Acetone: Acetone is a ketone.

Chemical Formula

Acetaldehyde: The chemical formula of acetaldehyde is C2H4O.

Acetone: The chemical formula of acetone is C3H6O.

Molar Mass

Acetaldehyde: The molar mass of acetaldehyde is 44.05 g/mol.

Acetone: The molar mass of acetone is 58.08 g/mol.

Melting Point and Boiling Point

Acetaldehyde: The melting point of acetaldehyde is −123.37 °C and the boiling point is 20.2 °C.

Acetone: The melting point of acetone is −94.7 °C and boiling point is 56.05 °C.

IUPAC Name

Acetaldehyde: The systematic IUPAC name for acetaldehyde is ethanal.

Acetone: The systematic IUPAC name for acetaldehyde is Propan-2-one.

Conclusion

Acetaldehyde and acetone are organic compounds. Both acetaldehyde and acetone are colorless liquid compounds. The main difference between acetaldehyde and acetone is that acetaldehyde is an aldehyde whereas acetone is a ketone.

References:

1. Brown, William H. “Acetaldehyde (CH3CHO).” Encyclopædia Britannica, Encyclopædia Britannica, inc., 20 Oct. 2014, Available here.
2. “Acetaldehyde.” Wikipedia, Wikimedia Foundation, 11 Dec. 2017, Available here.
3. “Acetone.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine, Available here.

Image Courtesy:

1. “Acetaldehyde-2D” By Benjah-bmm27 – Own work (Public Domain) via Commons Wikimedia
2. “Acetone-structural” By Ben Mills – High-resolution black and white PNG; ChemDraw / Photoshop (Public Domain) via Commons Wikimedia

About the Author: Madhusha

Madhusha is a BSc (Hons) graduate in the field of Biological Sciences and is currently pursuing for her Masters in Industrial and Environmental Chemistry. Her interest areas for writing and research include Biochemistry and Environmental Chemistry.

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