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What is the difference between an aldehyde and a ketone in terms of their chemical structure and properties? Provide examples of each and explain how they undergo reactions differently in Organic Chemistry.

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Aldehydes and ketones are both carbonyl compounds, which means they contain a carbon-oxygen double bond  C=O . The primary difference between them lies in the location of the carbonyl group and the types of atoms bonded to the carbonyl carbon.In an aldehyde, the carbonyl group is located at the end of a carbon chain and is bonded to a hydrogen atom and an alkyl group  or a hydrogen atom in the case of formaldehyde . The general structure of an aldehyde is R-CHO, where R represents an alkyl or aryl group. Examples of aldehydes include formaldehyde  HCHO , acetaldehyde  CH3CHO , and benzaldehyde  C6H5CHO .In a ketone, the carbonyl group is located within the carbon chain and is bonded to two alkyl or aryl groups. The general structure of a ketone is R-CO-R', where R and R' represent alkyl or aryl groups. Examples of ketones include acetone  CH3COCH3 , propanone  CH3COCH2CH3 , and acetophenone  C6H5COCH3 .Chemical Properties:1. Electrophilicity: Both aldehydes and ketones are electrophilic at the carbonyl carbon due to the polarization of the C=O bond. However, aldehydes are generally more reactive than ketones because the carbonyl carbon in aldehydes is bonded to a hydrogen atom, making it more electron-deficient and more susceptible to nucleophilic attack.2. Oxidation: Aldehydes can be easily oxidized to carboxylic acids, while ketones are generally resistant to oxidation. This is because the carbonyl carbon in aldehydes has a hydrogen atom that can be replaced by an oxygen atom during oxidation, whereas the carbonyl carbon in ketones is bonded to two alkyl or aryl groups, which cannot be replaced by an oxygen atom.Reactions:1. Nucleophilic Addition: Both aldehydes and ketones undergo nucleophilic addition reactions, where a nucleophile attacks the electrophilic carbonyl carbon. However, aldehydes are more reactive than ketones due to the presence of the hydrogen atom, which makes the carbonyl carbon more electron-deficient. Examples of nucleophilic addition reactions include the formation of cyanohydrins, Grignard reactions, and aldol condensation.2. Reduction: Aldehydes can be reduced to primary alcohols, while ketones can be reduced to secondary alcohols. The reduction of aldehydes and ketones can be achieved using reducing agents such as lithium aluminum hydride  LiAlH4  or sodium borohydride  NaBH4 .3. Oxidation: As mentioned earlier, aldehydes can be easily oxidized to carboxylic acids using oxidizing agents such as potassium permanganate  KMnO4  or chromic acid  H2CrO4 . Ketones, on the other hand, are generally resistant to oxidation.In summary, aldehydes and ketones differ in their chemical structure, with aldehydes having a carbonyl group bonded to a hydrogen atom and an alkyl or aryl group, while ketones have a carbonyl group bonded to two alkyl or aryl groups. Aldehydes are generally more reactive than ketones due to the presence of the hydrogen atom, which makes the carbonyl carbon more electron-deficient. Both aldehydes and ketones undergo nucleophilic addition and reduction reactions, but only aldehydes can be easily oxidized to carboxylic acids.

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