JEE Main 2019Chemistrys Block ElementsMediumMCQ

JEE Main 2019s Block Elements Question with Solution

JEE Main 2019 (12 Jan Shift 1)

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: D
Correct answer
DRb

Step-by-step explanation

K, Rb and Cs form super oxides on reaction with excess air

Rb+O2RbO2 (excess)

2RbO2+2H2O2RbOH+H2O2+O2

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About this question

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.