JEE Main 2021ChemistryHydrogenPreparation And Properties Of HydrogeneasyMCQ

JEE Main 2021 — Hydrogen Question with Solution

From: JEE Main 2021 (Online) 24th February Evening Shift

Question

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere.

Reason R : Hydrogen is the lightest element.

In the light of the above statements, choose the correct answer from the options given below :

Choose an option

Show full solutionCorrect option: B
Correct answer
BBoth A and R are true and R is the correct explanation of A

Step-by-step explanation

As we know, hydrogen is most abundant element in the universe but the most abundant gas in the troposphere is nitrogen, because hydrogen is lightest element.

Troposphere contains 3 quarters of mass of the entire atmosphere. The air here contain 78% nitrogen and 21% oxygen. The last 1% is made of argon, water vapour and carbon dioxide.

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About this question

This is a previous-year question from JEE Main 2021, covering the Hydrogen 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.