Question

Circle the odd one out. Give a reason for your choice.

• A. Hydrogen
• B. Nitrogen
• C. Oxygen
• D. Carbon dioxide

Answer 1

The correct option is A

Hydrogen

The explanation for the correct option -

Option (A) Hydrogen

• Air is made up of a mixture of gases.
• The main constituents of gases are nitrogen, oxygen, carbon dioxide, noble gases, water vapour, and dust particles.
• Hydrogen is not present in the composition of the air that is present around us.

The explanation for the incorrect option -

Option (B) Nitrogen - It is present by 78% by volume in the atmosphere.

Option (C) Oxygen - It is present by 21% by volume in the atmosphere.

Option (D) Carbon dioxide - It is present by 0.03% by volume in the atmosphere.

Nitrogen, oxygen, and carbon dioxide are the constituents of air that are present around us.

Therefore, Option (A) Hydrogen is the correct answer.