Question

64 About one-fifth of ordinary air is

• A. nitrogen
• B. carbon dioxide
• C. water vapor
• D. oxygen

Answer 1

The correct option is D

oxygen

The explanation for correct Option:

(D)-Oxygen

Air is made up of a mixture of various gases. Although we cannot see or smell the air, it is present all around us. Air is required for the survival of all living beings. Without air, living organisms cannot survive.

The major composition of air is oxygen, nitrogen, carbon dioxide, etc. It is composed of

Gases	Composition
Nitrogen	$78\%$
Oxygen	$20.95\%$
Hydrogen	$0.005\%$
Argon	$0.93\%$
Carbon dioxide	$0.04\%$
Neon	$0.0018\%$
Helium	$0.005\%$
Krypton	$0.0001\%$
Xenon	$8.7\times {10}^{-6}\%$

From the above table, about one-fifth of ordinary air is Oxygen

Final answer: The correct answer is an option (D)