JEE Main 2021 · ChemistryMultiple choiceSingle correctMediumConceptual

JEE Main 4 August 2021, Shift 1, Chemistry Q38

Question 38 of 90 in this shift, Chemistry question 8 of 30, Section A.

Choose the correct statement from the following :

(1)All group I compounds are diamagnetic.
(2)Pure $\mathrm{KO_2}$ is white and paramagnetic.
(3) $\mathrm{KO_2}$ is more stable than $\mathrm{LiO_2}$ .Official answer
(4)Among the alkali metal super oxides, $\mathrm{LiO_2}$ has the highest lattice energy.

Official answer

Option 3

NTA final key.

Chapter: The s-Block Elements
Topic: s-Block Elements
Idea tested: Formation of Oxides, Peroxides, and Superoxides

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