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Read the passage given below and answer ...

Read the passage given below and answer the questions that follow :
Aldehydes, ketones and carboxylic acids are some of the important classes of organic compounds containing carbonyl group. These are highly polar molecules due to higher electro-negativity of oxygen relative to carbon in the carbonyl group. Aldehydes are prepared by dehydrogenation or controlled oxidation of primary alcohols and controlled reduction of acyl halides. Ketones are prepared by oxidation of secondary alcohols and hydration of alkynes.
Aldehydes and ketones undergo nucleophilic addition reactions onto the carbonyl group but carboxylic acid does not undergo nucleophilic addition reaction. The alpha (`alpha`) - hydrogens of aldehydes and ketones are acidic. Therefore aldehydes and ketones having at least one a-hydrogen undergo Aldol condensation.
Aldehydes are easily oxidised by mild oxidising agents such as Tollens' reagent and Fehling's reagent. Carboxylic acids are prepared by the oxidation of primary alcohols, aldehydes and by hydrolysis of nitriles. Aromatic carboxylic acids are prepared by side-chain oxidation of alkyl benzenes. Carboxylic acids are considerably more acidic than alcohols and most of simple phenols
Arrange the following in the increasing order of their reactivity towards nucleophilic addition reaction :
`CH_3COCH_3, CH_3CHO, HCHO, C_6H_5COCH_3`

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A : Aldehydes and ketones undergo nucleophilic addition reaction. R : Aldehydes and ketones contain carbonyl group.

Read the passage given below and answer the following questions: Aldehydes, ketones and carboxylic acids are few of the major classes of organic compounds containing carbonyl group. Aldehydes are prepared by dehydrogenation or controlled oxidation of primary alcohols and controlled or selective reduction of acyl halides. Ketones are prepared by oxidation of secondary alcohols and hydration of alkynes. Carboxylic acids are prepared by the oxidation of primary alcohols, aldehydes and alkenes by hydrolysis of nitriles and by treatment of Grignard reagents with carbon dioxide. Name a method by which both aldehydes and ketones can be prepared.

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Read the passage given below and answer the following questions: Aldehydes, ketones and carboxylic acids are few of the major classes of organic compounds containing carbonyl group. Aldehydes are prepared by dehydrogenation or controlled oxidation of primary alcohols and controlled or selective reduction of acyl halides. Ketones are prepared by oxidation of secondary alcohols and hydration of alkynes. Carboxylic acids are prepared by the oxidation of primary alcohols, aldehydes and alkenes by hydrolysis of nitriles and by treatment of Grignard reagents with carbon dioxide. Through which of the following reactions number of carbon atoms can be increased in the chain?

Preparation of Aliphatic aldehyde and ketones

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Question based on preparation of aldehydes and ketones

Knowledge Check

  • A : Aldehydes and ketones undergo nucleophilic addition reaction. R : Aldehydes and ketones contain carbonyl group.

    A
    If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
    B
    If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
    C
    If Assertion is true statement but Reason is false, then mark (3).
    D
    If both Assertion and Reason are false statements, then mark (4).

  • Read the passage given below and answer the following questions: Aldehydes, ketones and carboxylic acids are few of the major classes of organic compounds containing carbonyl group. Aldehydes are prepared by dehydrogenation or controlled oxidation of primary alcohols and controlled or selective reduction of acyl halides. Ketones are prepared by oxidation of secondary alcohols and hydration of alkynes. Carboxylic acids are prepared by the oxidation of primary alcohols, aldehydes and alkenes by hydrolysis of nitriles and by treatment of Grignard reagents with carbon dioxide. Name a method by which both aldehydes and ketones can be prepared.

    A
    Reduction of carboxylic acids
    B
    Ozonolysis of alkenes
    C
    Oxidation of alcohols
    D
    All of the above

  • Read the passage given below and answer the following questions: Aldehydes, ketones and carboxylic acids are few of the major classes of organic compounds containing carbonyl group. Aldehydes are prepared by dehydrogenation or controlled oxidation of primary alcohols and controlled or selective reduction of acyl halides. Ketones are prepared by oxidation of secondary alcohols and hydration of alkynes. Carboxylic acids are prepared by the oxidation of primary alcohols, aldehydes and alkenes by hydrolysis of nitriles and by treatment of Grignard reagents with carbon dioxide. How will you distinguish between aliphatic aldehydes and aromatic aldehydes?

    A
    Fehling's test
    B
    Benedict's test
    C
    Iodoform test
    D
    Hinsberg reagent