Easy MCQ +4 / -1 PYQ · JEE Mains 2021

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 :

  1. A Both A and R are true but R is NOT the correct explanation of A
  2. B Both A and R are true and R is the correct explanation of A Correct answer
  3. C A is true but R is false
  4. D A is false but R is true.

Solution

<p>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.</p> <p>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.</p>

About this question

Subject: Chemistry · Chapter: p-Block Elements · Topic: Group 13: Boron Family

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