Atmosphere

Atmosphere

Atmosphere is defined as the mass or envelop of air surrounding the Earth.Atmosphere is composed of large amounts of nitrogen, hydrogen, and oxygen. The water present in the atmosphere is solid (snow, hail), liquid (rain) or gas (fog, mist).

Sources:

Die.net dictionary
En.MIMI
Ardictionary

Atmosphere gases

There are many atmospheric gases but nitrogen, oxygen, water vapour and carbon dioxide are the main gases found in the atmosphere.

For more read below:

Physical Geography
Ace.MMU
Blueyonder