Carbonyl vs. Carboxyl: What's the Difference?

Edited by Huma Saeed || By Sumera Saeed || Updated on October 21, 2023
Carbonyl is a functional group with a carbon-oxygen double bond (C=O); carboxyl has a carbonyl and hydroxyl group (COOH).

Key Differences
The carbonyl group is a characteristic feature of many organic compounds. It consists of a carbon atom double-bonded to an oxygen atom, denoted as C=O. This functional group can be found in various types of molecules, including aldehydes and ketones. On the other hand, the carboxyl group is a specific type of carbonyl that's bonded to a hydroxyl group, symbolized as COOH. This makes it an essential component in organic acids.

Sumera Saeed
Oct 21, 2023
Carbonyl compounds can be broadly categorized based on the position of the carbonyl group and the types of atoms bonded to the carbonyl carbon. For example, if the carbonyl carbon is bonded to a hydrogen and an alkyl group, it's an aldehyde. However, the presence of the carboxyl group immediately classifies a compound as a carboxylic acid, which is a subset of organic acids known for their acidic properties.

Sumera Saeed
Oct 21, 2023
In terms of reactivity, carbonyl compounds are typically reactive due to the polarity of the C=O bond. Electrophiles and nucleophiles can attack this bond, leading to a variety of chemical reactions. Conversely, the carboxyl group imparts acidity to carboxylic acids. This is because the hydrogen atom in the hydroxyl portion can be easily donated as a proton, making these compounds acidic.

Sumera Saeed
Oct 21, 2023
From a structural perspective, while both carbonyl and carboxyl groups contain a carbon-oxygen double bond, their behaviors in organic reactions differ considerably. The carbonyl group, being a simpler entity, engages in addition and oxidation reactions, among others. In contrast, the carboxyl group, due to its acidic nature, often undergoes reactions that involve the exchange of its proton, such as esterification.

Harlon Moss
Oct 21, 2023
To summarize, while the carbonyl group is a foundational entity found in a diverse range of organic molecules, the carboxyl group is a specialized version of a carbonyl, intrinsically linked to the acidic properties of carboxylic acids. The presence or absence of the hydroxyl group in conjunction with the carbonyl defines their differences.

Harlon Moss
Oct 21, 2023
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Comparison Chart
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Carbonyl and Carboxyl Definitions
Carbonyl
An entity found in various organic compounds like aldehydes and ketones.
The carbonyl in butanone gives it its distinctive properties.

Sumera Saeed
Oct 21, 2023
Carboxyl
A functional group found in carboxylic acids comprising a carbonyl and hydroxyl.
The carboxyl group in benzoic acid imparts its acidic nature.

Sumera Saeed
Oct 21, 2023
Carbonyl
A functional group characterized by a carbon-oxygen double bond.
Formaldehyde contains a carbonyl group, making it an aldehyde.

Huma Saeed
Oct 21, 2023
Carboxyl
An entity participating in reactions like esterification.
The carboxyl group in formic acid can react with alcohols to form esters.

Sara Rehman
Oct 21, 2023
Carbonyl
A polar group due to the differing electronegativities of carbon and oxygen.
The carbonyl's polarity makes it reactive towards nucleophiles.

Sara Rehman
Oct 21, 2023
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Carboxyl
A combination of carbonyl and hydroxyl functional groups.
The carboxyl in citric acid plays a crucial role in the citric acid cycle.

Huma Saeed
Oct 21, 2023
Carbonyl
A descriptor for compounds containing the C=O bond.
Carbonyl chlorides are used in the synthesis of certain polymers.

Sara Rehman
Oct 21, 2023
Carboxyl
A distinguishing feature making organic compounds acidic.
The carboxyl in propanoic acid can donate a proton.

Harlon Moss
Oct 21, 2023
Carbonyl
A central feature in many organic reactions.
The carbonyl in benzaldehyde is the site of nucleophilic attack.

Aimie Carlson
Oct 21, 2023
Carboxyl
A site of reactivity in various organic transformations.
The carboxyl in acetic acid can be reduced to form ethanol.

Sara Rehman
Oct 21, 2023
Carboxyl
The univalent group, -COOH, the functional group characteristic of all organic acids.

Sumera Saeed
Oct 23, 2019
Carboxyl
(organic chemistry) A univalent functional group consisting of a carbonyl and a hydroxyl functional group (-CO.OH); characteristic of carboxylic acids.

Sumera Saeed
Oct 23, 2019
Carboxyl
The complex radical, CO.OH, regarded as the essential and characteristic constituent which all oxygen acids of carbon (as formic, acetic, benzoic acids, etc.) have in common; - called also oxatyl.

Sumera Saeed
Oct 23, 2019
Carboxyl
The univalent radical -COOH; present in and characteristic of organic acids

Sumera Saeed
Oct 23, 2019
FAQs
In which compounds is the carbonyl group typically found?
Aldehydes, ketones, and many other organic compounds.

Sumera Saeed
Oct 21, 2023
What is the primary structural feature of a carbonyl?
A carbon-oxygen double bond (C=O).

Sumera Saeed
Oct 21, 2023
What's a simple test for carbonyl compounds?
The 2,4-dinitrophenylhydrazine (Brady's test) can detect carbonyl compounds.

Aimie Carlson
Oct 21, 2023
What happens when a carboxylic acid reacts with a strong base?
It forms a carboxylate salt.

Sumera Saeed
Oct 21, 2023
Are carboxyl groups found in amino acids?
Yes, amino acids have both amino and carboxyl functional groups.

Sara Rehman
Oct 21, 2023
How does the carboxyl group influence molecular polarity?
It increases polarity due to the electronegativity of both oxygen atoms.

Harlon Moss
Oct 21, 2023
Why are carboxylic acids considered acidic?
The carboxyl group can donate a proton.

Janet White
Oct 21, 2023
What's the significance of the carboxyl group in acids?
It imparts the acidic properties to carboxylic acids.

Aimie Carlson
Oct 21, 2023
What's a common reaction involving carbonyl compounds?
Addition reactions, especially with nucleophiles.

Sara Rehman
Oct 21, 2023
How do carboxylic acids typically react with alcohols?
Through esterification, producing esters.

Aimie Carlson
Oct 21, 2023
Are all compounds with a C=O bond considered carbonyl compounds?
Generally, yes, but context matters; carboxylic acids also have a C=O bond but are defined by the COOH group.

Sara Rehman
Oct 21, 2023
Are carbonyls present in sugars?
Yes, sugars can have aldehyde or ketone carbonyls, classifying them as aldoses or ketoses.

Sumera Saeed
Oct 21, 2023
How can one differentiate between aldehydes and ketones?
Both have carbonyls, but aldehydes have a hydrogen atom bonded to the carbonyl carbon, while ketones do not.

Sumera Saeed
Oct 21, 2023
How does a carboxyl group differ from a carbonyl?
It has an additional hydroxyl group (COOH).

Huma Saeed
Oct 21, 2023
Do carbonyl compounds participate in oxidation reactions?
Yes, especially aldehydes, which can be easily oxidized.

Aimie Carlson
Oct 21, 2023
Can carbonyl compounds form hydrogen bonds?
The carbonyl oxygen can accept hydrogen bonds, but the group itself cannot donate them.

Sumera Saeed
Oct 21, 2023
Are carboxylic acids soluble in water?
Many are, especially lower-molecular-weight acids, due to the ability of the carboxyl group to form hydrogen bonds with water.

Sumera Saeed
Oct 21, 2023
About Author
Written by
Sumera SaeedSumera is an experienced content writer and editor with a niche in comparative analysis. At Diffeence Wiki, she crafts clear and unbiased comparisons to guide readers in making informed decisions. With a dedication to thorough research and quality, Sumera's work stands out in the digital realm. Off the clock, she enjoys reading and exploring diverse cultures.

Edited by
Huma SaeedHuma is a renowned researcher acclaimed for her innovative work in Difference Wiki. Her dedication has led to key breakthroughs, establishing her prominence in academia. Her contributions continually inspire and guide her field.
