Question

Circle the odd one out. Give reasons for your choice.

• A. Methane
• B. Water vapour
• C. Carbon dioxide
• D. Nitrogen

Answer 1

The correct option is A

Methane

The explanation for the correct option -

Option (A) Methane - It is not a constituent of air.

The explanation for the incorrect option -

Option (B) Water vapour - It is a variable constituent of air.

Option (C) Carbon dioxide - It is a constituent of air and presents 0.03% of air by volume.

Option (D) Nitrogen - It is a constituent of air and presents 71% of air by volume.

Therefore, Option (A) i.e Methane is the correct answer.