Learn

Saturday, 31 October

JEE Main 2026 · ChemistryMultiple choiceSingle correctHardMulti-step

JEE Main 6 April 2026, Shift 2, Chemistry Q69

Question 69 of 75 in this shift, Chemistry question 19 of 25, Section A.

Consider the following reactions. Total number of electrons in the π\pi bonds and lone pair of electrons in the product (X) is : [figure: open-chain glucose] CHO−(CHOH)4−CH2OH\mathrm{CHO{-}(CHOH)_4{-}CH_2OH} →(i) HI, Δ; (ii) V2O5/10-20 atm/773 K; (iii) Benzoyl chloride/Anhyd. AlCl3\xrightarrow{\text{(i) HI, }\Delta;\ \text{(ii) V}_2\mathrm{O}_5/10\text{-}20\text{ atm}/773\text{ K};\ \text{(iii) Benzoyl chloride/Anhyd. AlCl}_3} (X) Major product

The figure, in words

Open-chain glucose CHO-(CHOH)4-CH2OH drawn vertically, with reagents (i) HI, Δ; (ii) V2O5/10-20 atm/773 K; (iii) benzoyl chloride/anhyd. AlCl3 giving (X).
  1. (1)12
  2. (2)16
  3. (3)14
  4. (4)18Official answer

Official answer

Option 4

NTA final key.

Chapter
Biomolecules
Topic
Carbohydrates
Idea tested
Reduction with HI and Red Phosphorus

Same idea in other shifts

Asked 2× in all
  1. 27 Jul 2022, Shift 2 · Q77Match **List - I** with **List - II**. List - I (A) Glucose + HI (B) Glucose + Br2\mathrm{Br_2} water (C) Glucose + acetic anhydride (D)…MediumMatch the list

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.