JEE Main 2021 — S Block Elements Question with Solution
From: JEE Main 2021 (Online) 20th July Morning Shift
Question
A s-block element (M) reacts with oxygen to form an oxide of the formula MO2. The oxide is pale yellow in colour and paramagnetic. The element (M) is :
Choose an option
Show full solutionCorrect option: D
Correct answer
DK
Step-by-step explanation
The element (M) is potassium (K). It reacts with O2 to form KO2, which is paramagnetic in nature. All other elements form oxides or peroxides which are diamagnetic in nature.
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This is a previous-year question from JEE Main 2021, covering the S Block Elements chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.