Difference WikiChemistry

Difference Between Aldehyde and Ketone

Main Difference

The main difference between Aldehyde and Ketone is that Aldehyde’s carbonyl group is attached to an alkyl group from one side and with H atom from the other side, whereas the carbonyl group of the Ketone is attached to two alkyl groups from its either sides.

Aldehyde vs. Ketone

Aldehyde considered an organic compound containing the general chemical formula R-CHO, while ketone is considered an organic compound containing the general chemical formula R-CO-R. Aldehyde is generally more reactive as compared to ketone and undergo oxidation producing carboxylic acids. In contrast, ketone, without infringement of the carbon chain, cannot be oxidized and is less reactive than aldehyde.

The IUPAC name of aldehyde end with a suffix ‘al’; on the other hand, the IUPAC name of ketone end with the suffix ‘one.’ The aldehyde is always present at the end of a carbon chain; on the contrary, the ketone is ordinarily present in the middle of the chain.

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Aldehyde is naturally found in volatile compounds, for example, fragrance compounds; on the flip side, the ketone has naturally occurred in sugars. The aldehyde, which is present in sugars, are aldehyde sugars and are known as aldoses; conversely, the ketone, which is present in sugars, are known as ketoses in general.

Comparison Chart

AldehydeKetone
Aldehyde is an organic compound whose carbonyl group bonded with an alkyl group from one side and with hydrogen from the other side.Ketone is an organic compound whose carbonyl group is attached to two alkyl groups from one or both sides.
Chemical Structure
Containing the general chemical formula R-CHOContaining the general chemical formula R-CO-R
Reactivity
More reactive as compared to ketonesLess reactive than aldehyde
Oxidation
Undergo oxidation producing carboxylic acidscannot be oxidized without breaking the carbon chain
IUPAC Nomenclature
The IUPAC name end with a suffix ‘al.’The IUPAC name end with the suffix ‘one.’
Location of Carbonyl Group
Always present at the end of a carbon chainNormally present in the middle of the chain
Natural Occurrence
Naturally found in volatile compounds for example fragrance compoundsNaturally occurred in sugars
Aldoses/Ketoses
Present in sugars are aldehyde sugars and are known as aldosesPresent in sugars are known as ketoses in general
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What is Aldehyde?

The aldehyde can define through its chemical structure R-CHO in which C atom attached with oxygen atom through a double bond (R-(C=O)-H). Hence, one end side of the carbonyl group of aldehyde is always an H atom, and the other side is attached to the alkyl group.

The aldehyde groups found at the end of the carbon chain. Hence, if a carbonyl group is present at the end of the carbon chain, then it means it is an aldehyde. As aldehydes form acetaldehyde and formaldehyde, so they are extremely useful chemical compounds in the industries.

The aldehyde considered more reactive than ketone because it displays varying results when combines with chemical reagents. The aldehyde goes through the oxidization and produces carboxylic acid, and it can reduce to form alcohol.

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Liable on the nature of the carbon chain from which the aldehyde attached to, many other numerous functions occur. According to the IUPAC names, when naming aldehydes, the aldehydes always end with a suffix “al.” therefore, the names of the aldehydes of the corresponding alkyl group are, butanal, propanal, hexanal, etc.

The aldehyde can differentiate from a ketone through several laboratory tests such as the Schiff’s test, Tollen’s test, and Fehling’s test is one of the famous tests for aldehyde. For instance, during Fehling’s test, the ketone does not show any reaction while aldehyde forms red precipitates.

Aldehydes consider more electrophilic because they do not consist of an electron giving the effect of an alkyl group. Also, aldehydes give many problems during its synthesis. As concern for their non-acidic proton, the aldehydes can be hard to remove for substitution.

What is Ketone?

The ketone can explain by its chemical formula R-CO-R in which C atom attached with the oxygen atom through the double bond. As the carbonyl group of ketones surrounded with alkyl groups that can be aliphatic, olefinic, or aromatic on its both sides or maybe one end contains benzene rings, so a ketone is never being available at the end of a carbon chain.

Ketones considered less reactive than aldehydes because it usually doesn’t give any reaction. Though ketones mostly used as industrial solvents such as acetones, the ketones cannot be oxidized any further because they are already present in their highest oxidation form, but they can go through reducing reactions to form the corresponding alcohols.

It is very easy to recognize the ketones through their IUPAC names in which the ketone is ended with a suffix ‘one.’ For instance, heaxanone, pentanone, butanone, etc. Ketones contain double bonds everywhere in the chain except for the end, so one can find the ketone in the middle of the chain in which the double bond of oxygen will attach to one of the carbon atoms.

The ketones are naturally occurring in sugars in which they are known as ketoses. The ketones can be distinguished by some laboratory tests which is done by using Tollen’s reagent that made using silver nitrate and an amount of sodium hydroxide and a little bit of dilute ammonia, which act as an oxidizing agent.

When Tollen’s reagent added to a ketone, no results will find. But if the same solution added to aldehyde, it will from silver precipitates because the aldehyde oxidized into a carboxylic acid, which ketone cannot. This reaction is seemed very pretty if done well because the container will turn into lined with silver.

Key Differences

  1. An organic compound that contains the general formula of its chemical structure is R-CHO is known as aldehyde; on the other hand, the organic compound, which consists of the general formula of its chemical structure, is R-CO-Ris known as ketone.
  2. The aldehyde usually contains one alkyl group on its one side and a hydrogen atom on its other side; on the contrary, a ketone contains two alkyl groups present on its either side.
  3. The aldehyde is considered more reactive than ketone because it displays varying results when combines with chemical reagents; on the flip side, the ketone is deliberated less reactive than aldehyde because it usually doesn’t give any reaction.
  4. According to the IUPAC name of aldehyde, it ends with the suffix ‘al’; conversely, according to the IUPAC name of ketone, it ends with the suffix ‘one.’
  5. The aldehyde goes through oxidization and produces carboxylic acid; on the other hand, the ketones don’t undergo the process of oxidization.
  6. The aldehyde contains carbonyl groups that are present at the end of the carbon chain; on the contrary, ketone contains carbonyl groups normally present in the middle of the chain.
  7. Aldehydes are naturally occurring in volatile compounds such as fragrance compounds, while ketones are naturally found in sugars and known as ketoses in general.

Conclusion

The above discussion concludes that both aldehyde and ketone contains the carbonyl groups. The difference between them is that aldehyde contains an alkyl and a hydrogen atom, while the ketone contains two alkyl groups on both the side.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss