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What is the difference between an aldehyde and a ketone? Give three examples of each and explain what makes them different from each other in terms of chemical structure and reactivity. Additionally, provide a brief explanation of common methods for synthesizing both aldehydes and ketones.

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Aldehydes and ketones are both organic compounds containing a carbonyl group  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 bonded to a hydrogen atom and an alkyl or aryl group. The general formula for an aldehyde is RCHO, where R represents an alkyl or aryl group. Aldehydes are generally more reactive than ketones due to the presence of the hydrogen atom, which makes them more susceptible to nucleophilic attack.Examples of aldehydes:1. Formaldehyde  HCHO  - the simplest aldehyde, used as a disinfectant and preservative.2. Acetaldehyde  CH3CHO  - an intermediate in alcohol metabolism and a common ingredient in industrial processes.3. Benzaldehyde  C6H5CHO  - an aromatic aldehyde with the smell of almonds, used as a flavoring agent and in the synthesis of other chemicals.In a ketone, the carbonyl group is bonded to two alkyl or aryl groups. The general formula for a ketone is RCOR', where R and R' represent alkyl or aryl groups. Ketones are generally less reactive than aldehydes due to the absence of the hydrogen atom, which makes them less prone to nucleophilic attack.Examples of ketones:1. Acetone  CH3COCH3  - the simplest ketone, used as a solvent and in the production of plastics and other chemicals.2. Butanone  CH3CH2COCH3  - a common solvent and an intermediate in the synthesis of other chemicals.3. Cyclohexanone  C6H10CO  - a cyclic ketone used as a solvent and in the production of nylon.Synthesis of aldehydes and ketones:1. Oxidation of alcohols: Primary alcohols can be oxidized to aldehydes, and secondary alcohols can be oxidized to ketones using oxidizing agents such as chromium VI  compounds  e.g., Jones reagent, pyridinium chlorochromate  or other milder reagents like Dess-Martin periodinane or Swern oxidation.2. Ozonolysis of alkenes: The reaction of alkenes with ozone followed by reductive workup can produce aldehydes and ketones, depending on the substitution pattern of the alkene.3. Friedel-Crafts acylation: The reaction of an acyl halide with an aromatic compound in the presence of a Lewis acid catalyst  e.g., AlCl3  can produce aromatic ketones.4. Nucleophilic acyl substitution: The reaction of an acyl halide or anhydride with an organometallic reagent  e.g., Grignard reagent or organolithium compound  can produce ketones.These are just a few examples of the many methods available for synthesizing aldehydes and ketones. The choice of method depends on the specific reactants and desired products, as well as the reaction conditions and available resources.

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