Air

Air is an important form of inexhaustible natural resource which is essential for our survival. In a world without air, there would be no plant or animal life; no fire as burning needs oxygen; no protection from harmful solar radiation; and great temperature variation (from about 110° C at day time to about – 184°C at night).So, atmosphere (air) is a transport protective envelope of gases that surrounds the earth.

Composition of Atmosphere

Nitrogen (N₂) : 78%

Oxygen (O₂) : 21%

Carbon dioxide (CO₂) : 0.03%

Argon : 0.93% 1%

Helium, Neon, Ozone, ammonia : 0.04%

Role of Atmosphere (Air)

• Atmosphere provides :
• Oxygen for respiration in plants and animals
• CO₂ for photosynthesis
• Medium for locomotion of flying animals
• Medium for communication
• Medium for combustion (oxygen is required for combustion)