Question

1. Briefly state the importance of following constituents of air :

(a) Oxygen

Answer 1

The amount of oxygen in the air varies between 20.8% to 20.9% by volume.

Significance of oxygen in the atmosphere :

• Oxygen supports all animal and plant life on the earth, as it supports respiration.
• Man burns an enormous amount of fuel for his energy needs. Oxygen is essential for the burning of fuels.
• Oxygen dissolves to some extent in water. This enables aquatic plants and animals to breathe.