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Saturday, 31 October

JEE Main 2023 · ChemistryMultiple choiceDiagram basedMediumData or graph

JEE Main 6 April 2023, Shift 2, Chemistry Q63

Question 63 of 90 in this shift, Chemistry question 3 of 30, Section A.

Consider the following reaction that goes from A to B in three steps as shown below: Choose the correct option Number of intermediates | Number of Activated complexes | Rate determining step

The figure, in words

Energy vs Reaction Coordinate profile from A to B with three humps (Step I, Step II, Step III); the second hump (Step II) is the tallest, the first and third are lower; B ends lower than A.
  1. (1)2 | 3 | IIOfficial answer
  2. (2)2 | 3 | III
  3. (3)3 | 2 | II
  4. (4)2 | 3 | I

Official answer

Option 1

NTA final key.

Chapter
Chemical Kinetics
Topic
Arrhenius Equation
Idea tested
Reaction Energy Profiles

Same idea in other shifts

Asked 4× in all
  1. 2 Apr 2025, Shift 2 · Q56Reactant A converts to product D through the given mechanism (with the net evolution of heat) : A→BA \rightarrow B slow; ΔH=+\Delta H = +ve…MediumDiagram basedHas a figure
  2. 8 Apr 2023, Shift 2 · Q63The correct reaction profile diagram for a positive catalyst reaction.EasyDiagram basedHas a figure
  3. 31 Aug 2021, Shift 1 · Q53According to the following figure, the magnitude of the enthalpy change of the reaction A+B→M+N\mathrm{A+B\rightarrow M+N} in kJ mol−1^{-1} is…MediumNumerical valueHas 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.