JEE Main 2022 · ChemistryMultiple choiceSingle correctMediumConceptual

JEE Main 26 June 2022, Shift 2, Chemistry Q68

Question 68 of 90 in this shift, Chemistry question 8 of 30, Section A.

Which one of the following is an example of disproportionation reaction ?

(1) $3\mathrm{MnO_4^{2-}} + 4\mathrm{H^+} \rightarrow 2\mathrm{MnO_4^-} + \mathrm{MnO_2} + 2\mathrm{H_2O}$ Official answer
(2) $\mathrm{MnO_4^-} + 4\mathrm{H^+} + 4e^- \rightarrow \mathrm{MnO_2} + 2\mathrm{H_2O}$
(3) $10\mathrm{I^-} + 2\mathrm{MnO_4^-} + 16\mathrm{H^+} \rightarrow 2\mathrm{Mn^{2+}} + 8\mathrm{H_2O} + 5\mathrm{I_2}$
(4) $8\mathrm{MnO_4^-} + 3\mathrm{S_2O_3^{2-}} + \mathrm{H_2O} \rightarrow 8\mathrm{MnO_2} + 6\mathrm{SO_4^{2-}} + 2\mathrm{OH^-}$

Official answer

Option 1

NTA final key.

Chapter: Redox Reactions
Topic: Redox Reactions
Idea tested: Disproportionation Balancing

Same idea in other shifts

Asked 7× in all

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