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Karnataka Board PUCPUC Science 2nd PUC Class 12

An aromatic compound ‘A’ (Molecular formula [\ce{C8H8O}]) gives positive 2, 4-DNP test. It gives a yellow precipitate of compound ‘B’ on treatment with iodine and sodium hydroxide soluti - Chemistry

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Question

An aromatic compound ‘A’ (Molecular formula \[\ce{C8H8O}\]) gives positive 2, 4-DNP test. It gives a yellow precipitate of compound ‘B’ on treatment with iodine and sodium hydroxide solution. Compound ‘A’ does not give Tollen’s or Fehling’s test. On drastic oxidation with potassium permanganate it forms a carboxylic acid ‘C’ (Molecular formula \[\ce{C7H6O2}\]), which is also formed along with the yellow compound in the above reaction. Identify A, B and C and write all the reactions involved.

Long Answer
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Solution

Molecular formula of compound is \[\ce{C8HgO}\]. As ‘A’ does not give Tollens’ or Fehling’s test. It must be a ketone. It gives positive test with 2, 4-DNP and iodoform test. It means it is methyl ketone.

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Chapter 12: Aldehydes, Ketones and Carboxylic Acids - Multiple Choice Questions (Type - I) [Page 176]

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NCERT Exemplar Chemistry [English] Class 12
Chapter 12 Aldehydes, Ketones and Carboxylic Acids
Multiple Choice Questions (Type - I) | Q 48 | Page 176

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