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Saturday, 31 October

JEE Main 2026 · ChemistryMultiple choiceDiagram basedMediumConceptual

JEE Main 4 April 2026, Shift 1, Chemistry Q70

Question 70 of 75 in this shift, Chemistry question 20 of 25, Section A.

Identify the colour of compound 'X' in the sequence of the reaction.

The figure, in words

Reaction scheme: 2 phenol + phthalic anhydride with conc. H2SO4\mathrm{H_2SO_4} gives phenolphthalein (lactone form with two 4-hydroxyphenyl groups); with NaOH gives the pink quinoid form (one phenoxide, one quinone-type =O, carboxylate COO−\mathrm{COO^-}) labelled (Pink); with excess NaOH gives X: a carbinol (central C bearing OH) with two O−\mathrm{O^-} phenoxide rings and an ortho COO−\mathrm{COO^-} on the third ring.
  1. (1)Violet
  2. (2)Green
  3. (3)Red
  4. (4)ColourlessOfficial answer

Official answer

Option 4

NTA final key.

Chapter
Alcohols, Phenols and Ethers
Topic
Alcohols and Phenols
Idea tested
Phthalein Dye Test

Same idea in other shifts

Asked 4× in all
  1. 8 Apr 2023, Shift 2 · Q75A compound 'X' when treated with phthalic anhydride in presence of concentrated H2SO4\mathrm{H_2SO_4} yields 'Y'. 'Y' is used as an acid/base…EasySingle correct
  2. 26 Aug 2021, Shift 2 · Q50Which one of the following phenols does not give colour when condensed with phthalic anhydride in presence of conc. H2SO4\mathrm{H_2SO_4} ?EasyDiagram basedHas a figure
  3. 24 Feb 2021, Shift 1 · Q40Which of the following compound gives pink colour on reaction with phthalic anhydride in conc. H2SO4\mathrm{H_2SO_4} followed by treatment…EasySingle correctHas a figure

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 108 of the 174 JEE Main shifts held from 2017 to 2026.