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Friday, 9 October

JEE Main 2022 · ChemistryMultiple choiceSingle correctEasyConceptual

JEE Main 24 June 2022, Shift 1, Chemistry Q75

Question 75 of 90 in this shift, Chemistry question 15 of 30, Section A.

Which of the following is an example of conjugated diketone ?

The figure, in words

Options are drawn structures of diketones.
  1. (1)CH3−CO−CH2−CH2−CH2−CO−CH3\mathrm{CH_3-CO-CH_2-CH_2-CH_2-CO-CH_3}
  2. (2)CH3−CO−CH2−\mathrm{CH_3-CO-CH_2-}(cyclohexan-4-one ring, C=O at the para position of the ring)
  3. (3)[figure: 1,4-benzoquinone, ring with two C=O groups para to each other]Official answer
  4. (4)[figure: C6H5−CO−CH2−CH2−CO−CH3\mathrm{C_6H_5-CO-CH_2-CH_2-CO-CH_3}]

Official answer

Option 3

NTA final key (2022 Session 1).

Chapter
Aldehydes, Ketones and Carboxylic Acids
Topic
Alcohols and Phenols
Idea tested
Phenol Oxidation to Benzoquinone

Same topic in other shifts

All Alcohols and Phenols questions
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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.