JEE Main 2019 — S Block Elements Question with Solution
From: JEE Main 2019 (Online) 12th January Morning Slot
Question
A metal on combustion in excess air forms X. X upon hydrolysis with water yields H2O2 and O2 along with another product. The metal is :
Choose an option
Show full solutionCorrect option: A
Correct answer
ARb
Step-by-step explanation
K, Rb and Cs form super oxides on reaction with excess
air.
Rb + O2 RbO2
2RbO2 + 2H2O 2RbOH + H2O2 + O2
Rb + O2 RbO2
2RbO2 + 2H2O 2RbOH + H2O2 + O2
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This is a previous-year question from JEE Main 2019, 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.