What Is Acetone and Why Is It Important in Chemistry?
Acetone, also known as dimethyl ketone and propanone, is the simplest, smallest, and most important of all the aliphatic (fat-derived) ketones. Pure acetone is a colorless, clear liquid. It is somewhat aromatic with a pleasant fruity odor and is a volatile, flammable liquid.
Let us discuss more details about the structure, uses, and properties of Acetone from this article.
Properties
Acetone is a highly miscible liquid. It readily dissolves in substances like water, ethanol, ether etc. Its freezing point is −94.7 °C. Its boiling point is 56.05 °C, while its flash point is −20 °C. Its molecular formula is CH3COCH3. Its IUPAC name is Propan-2-one. Acetone can dissolve many fats and multiple resins as well as substances like cellulose acetate, nitrocellulose, and other cellulose ethers.
Occurrance
Acetone naturally occurs in plants, trees, volcanic gases, forest fires, and as a product of the breakdown of body fat. It is also found in small quantities in normal urine and blood, while the concentration may be higher in diabetic patients. We can detect traces of it in vehicle exhaust, tobacco smoke, and landfill sites. It is found among the many products formed in the destructive distillation of materials like wood, sugar, and cellulose, etc.
The organic compound for the Acetone, or the Propanone, has the formula (CH3)2CO. It is important for the students of Chemistry to learn about Acetone, and for learning the topic of Acetone, students are required to have a good explanation of the same as well, so that the process of learning becomes easy for the students. And hence Vedantu provides the students with such an explanation of the topic of Acetone, which is easy to understand and comprehend, and it includes everything about the topic of Acetone, such as its structure, Uses and Properties.
An Overview of the Acetone
As said earlier, Acetone is also known as Propanone, and its chemical formula is (CH3)2CO. Let us understand the meaning of Ketone is a functional group in Chemistry, and has R2C=O, where any carbon-containing substituents can be represented by R. Now coming to the Acetone, it is also a Ketone, and of all the ketone, Acetone is one of the simplest and smallest ketones. Acetone is a highly volatile, colorless, flammable liquid, which has a pungent odor.
With water Acetone is miscible, that is to say, it mixes with water in all the proportions and thus forms a homogeneous mixture. In many industries, Acetone serves the purpose of an important organic solvent, and along with the industries it does the same in households and laboratories. For household items, Acetone is an active ingredient in items like nail polish remover, paint thinner.
History of Acetone
Acetone was first produced and used by alchemists during the late Middle Ages. The method of manufacture at that time was via the dry distillation of metal acetates, like lead acetates. It was also called the ‘spirit of Saturn’ because it was primarily produced with lead acetate, which contains lead. Lead has the same symbol as the astrological symbol for the planet Saturn.
French chemist Jean-Baptise Dumas and German chemist Justus von Liebig determined the empirical formula for acetone in 1832. French chemist Antoine Bussy named acetone by adding the suffix -one to the stem of the corresponding acid, that is acetic acid in 1833. In 1852, an English chemist named Alexander William Williamson realized that acetone was nothing but methyl acetyl. French chemist Charles Fredric concurred with the findings of Williams in the following year. In 1861 Johann Josef Loschmidt presented the structure of acetone but he did not receive any attention at that time. German Chemist August Kekule published the modern structural formula for acetone in 1865. Chaim Weizmann developed the process for the industrial production of acetone during World War I. This process is widely used to this day and is known as the Weizmann Process.
Ca (CH3COO)2 → CaO(s) + CO2(g) + (CH3)2CO
Production of Acetone
Acetone is mostly produced directly or indirectly from propylene. Roughly 83% of acetone is produced by the cumene process. Since this process requires phenol, acetone production is tied to phenol production. In the cumene process, benzene is treated with alkaline propylene to produce cumene, which is oxidized by air to produce phenol and acetone.
Other than this method, the direct oxidation of propylene (also known as the Wacker-Hoechst process) or the hydration of propylene to give propanol, which can be oxidized to acetone can also be used.
The United States has the highest production capacity of acetone, followed by Taiwan and China. The largest company which produces acetone is INEOS Phenol, owning 17% of the world’s capacity. It also owns the world’s largest production site, in Beveren, Belgium, which has the capacity to produce 420,000 tonnes each year.
Uses of Acetone
Solvent
Chemical Intermediate
Laboratory Use
Medical and Cosmetic Uses
Other Domestic uses
Solvent – Acetone is a good usable solvent for many plastics and a few synthetic fibers. It is used to dissolve two-part epoxies and superglue before they harden. It is also used for thinning polyester resin and cleaning tools with it. It is used in paints and varnishes as a volatile component. It is useful in the preparation of metal before painting as a heavy-duty degreaser. It is used to remove rosin flux after high-reliability soldering applications, and thus prevent the rusty bolt effect.
Acetone also functions as a solvent in the pharmaceutical industry and is used as a denaturant in denatured alcohols. Acetone is also present as an excipient in multiple pharmaceutical drugs
Although it is somewhat flammable, acetone is used as a solvent during the storage and transportation of acetylene, which cannot be pressurized as a pure compound. Hence acetylene is dissolved in acetone while being transported. One-third of the world's acetone is used as a solvent.
Chemical Intermediate – Acetone is used to synthesize compounds like methyl methacrylate. It involves a conversion of acetone to acetone cyanohydrin, followed by nitrite being hydrolyzed to an unsaturated amide, which is then esterified.
(CH3)2CO + HCN → (CH3)2C(OH)CN
(CH3)2C(OH)CN + CH3OH → CH2=(CH3) CCO2CH3 + NH3
Synthesis of bisphenol A is another major use of acetone. Many polycarbonates, polyurethanes, and epoxy resins constitute bisphenol-A. The synthesis of bisphenol A involves the condensation of phenol along with acetone.
(CH3)2CO + 2 C6H5OH → (CH3)2C(C6H4OH)2 + H2O
Another major use of acetone is in the production of solvents methyl isobutyl alcohol and methyl isobutyl ketone. These products arise through the process of aldol condensation and give diacetone alcohol.
2 (CH3)2CO → (CH3)2C(OH)CH2C(O)CH3
Laboratory Use – Acetone functions as a polar aprotic solvent in a variety of organic reactions such as SN2 reactions in the laboratory. In the process of Jones oxidation, the use of acetone is critical. It does not form an azeotrope with water, which means it has a different boiling point than water when dissolved in it. Added to this its low cost and volatility, it is commonly used as a rinsing agent in laboratory glassware. Acetone can be cooled to a low temperature up to −78 °C by using dry ice, hence is used to conduct reactions at a lower temperature. Since acetone is fluorescent under ultraviolet light, its vapor is an ideal fluorescent tracer in fluid flow experiments. Acetone is also sometimes used as a precipitator for proteins.
Medical and Cosmetic Use – Acetone is widely used in many general medicines and cosmetic products. It is also a component listed as a food additive and used in nail polish remover and paints thinner. Dermatologists for acne treatments use acetone to peel off dry skin.
Acetone is also used in chemical peeling treatments. Prior to chemexfoliation, acetone is used to clean the skin and remove excess fat.
Other Domestic Uses – Acetone is used in nail polish remover and paint thinners. Acetone is a component of superglue remover too. It also removes residue from glass and porcelain. It is also used by makeup artists to remove skin adhesives.
Vapor polishing of printing artifacts on 3-D printed models applies acetone. This technique is called acetone vapor bath smoothing. Low-grade acetone is also sometimes used as a glassware rinsing agent for removing residue in academic laboratories before a final wash.
Extra-terrestrial Occurrence of Acetone
On 30 July 2015, upon the first touchdown of Philae lander on the surface of comet 67P, scientists reported that measurements by COSAC and Ptolemy instruments revealed sixteen organic compounds on the surface of the comet. Four of these organic compounds were not seen on any other comet before this occasion. One of the four organic compounds happened to be acetone.
FAQs on Acetone: Structure, Properties, and Everyday Uses
1. What is acetone, and what is its IUPAC name?
Acetone is a simple organic compound and the smallest member of the ketone family. It is a colorless, volatile, and flammable liquid. According to the International Union of Pure and Applied Chemistry (IUPAC) nomenclature, its official name is propan-2-one.
2. What is the chemical formula and structure of acetone?
The chemical formula for acetone is C₃H₆O. Its structure consists of a central carbonyl group (a carbon atom double-bonded to an oxygen atom, C=O), which is bonded to two methyl groups (-CH₃). The structural formula is often written as (CH₃)₂CO. This trigonal planar geometry around the carbonyl carbon is key to its chemical properties.
3. What are the main physical properties of acetone?
Acetone exhibits several distinct physical properties that are important for its applications:
Appearance: It is a colorless liquid at room temperature.
Odor: It has a characteristic sweet, pungent smell.
Solubility: It is miscible (can be mixed in any proportion) with water, ethanol, and ether.
Boiling Point: It has a relatively low boiling point of 56°C (133°F), which makes it highly volatile.
Density: It is less dense than water.
4. What are some common everyday uses of acetone?
Acetone is a versatile solvent with numerous applications in both household and industrial settings. Some common examples of its use include:
As the primary active ingredient in nail polish remover.
As a powerful solvent in paint and varnish strippers.
For cleaning and degreasing tools, equipment, and laboratory glassware.
In the industrial manufacturing of plastics, fibres, and other chemicals like methyl methacrylate and bisphenol A (BPA).
As a solvent and excipient in the pharmaceutical industry.
5. How is acetone prepared on a large scale for industrial use?
The primary commercial method for producing acetone is the Cumene Process. This multi-step process involves the alkylation of benzene with propene to produce cumene (isopropylbenzene). The cumene is then oxidized by air to form cumene hydroperoxide. Finally, this hydroperoxide is treated with an acid (like sulfuric acid) to yield two valuable products: phenol and acetone. This method is highly efficient and accounts for the majority of global acetone production.
6. Why is acetone such an effective solvent for a wide range of substances?
Acetone's effectiveness as a solvent stems from its molecular structure, making it a polar aprotic solvent. The carbonyl group (C=O) is polar, which allows it to dissolve other polar substances like water and alcohols. Simultaneously, the two non-polar methyl (-CH₃) groups on either side allow it to dissolve many non-polar substances such as oils, greases, and certain plastics. This dual nature allows it to mix with both polar and non-polar compounds, making it a highly versatile and widely used solvent.
7. How does the carbonyl group in acetone influence its chemical reactivity?
The carbonyl group (C=O) is the functional group that dictates acetone's chemical behaviour. Due to the higher electronegativity of oxygen, the C=O bond is highly polarized. This polarization makes the carbonyl carbon atom electrophilic (electron-deficient) and the carbonyl oxygen atom nucleophilic (electron-rich). Consequently, acetone's most characteristic reaction is nucleophilic addition, where a nucleophile attacks the electron-deficient carbon atom, breaking the pi bond of the carbonyl group.
8. What is the main difference between acetone and other ketones like butanone?
The primary difference is that acetone (propan-2-one) is the simplest possible ketone. Its carbonyl carbon is bonded to two identical methyl groups (-CH₃). In contrast, other ketones like butanone (or methyl ethyl ketone) have different alkyl groups attached; butanone has one methyl group and one ethyl group (-CH₂CH₃) bonded to the carbonyl carbon. This structural simplicity makes acetone less sterically hindered, which can influence its reactivity compared to larger, bulkier ketones.
9. What are the potential hazards of using acetone, and what safety precautions are necessary?
While common, acetone must be handled with care due to its potential hazards. It is highly flammable, and its vapours can form explosive mixtures with air. It can also cause moderate to severe irritation to the eyes, nose, and throat. To ensure safety, you should:
Use it in a well-ventilated area to prevent vapour accumulation.
Keep it far away from open flames, sparks, and heat sources.
Wear personal protective equipment (PPE) like safety goggles and chemical-resistant gloves.
Store it in a cool, dry place in a tightly sealed and properly labelled container.
10. Can acetone undergo an aldol condensation reaction? Explain the reason.
Yes, acetone can undergo an aldol condensation reaction. The requirement for this reaction is the presence of at least one alpha-hydrogen—a hydrogen atom on the carbon adjacent to the carbonyl group. Acetone, (CH₃)₂CO, has six alpha-hydrogens (three on each of its two methyl groups). In the presence of a suitable base, one of these acidic alpha-hydrogens can be removed to form a reactive enolate ion. This ion then acts as a nucleophile, attacking another acetone molecule to initiate the condensation process, eventually forming diacetone alcohol.
