2nd Class EVS Weather, Air and Water Air as a Mixture of Gases

     Introduction

Weather of a place is influenced by the condition of air and quantity of available water. Air is the mixture of different gases. Water is the chemical composition of hydrogen and oxygen. Both water and air is most important for living organism on the earth. Air always moves from high pressure area to low pressure area. This motion of air is called wind. In this chapter we will study about air, water and weather.

     Air as a Mixture of Gases

Air is not man made. It is a natural resource, and it is present everywhere. It cannot. be seen, and it is not exhaustible. Air is very important for living things because without air a living organism will die. This is the reason why air is called invisible friend of living organisms. Air is not a single component. In fact it is a mixture of different gases like nitrogen, oxygen, carbon dioxide, hydrogen, arson, neon, helium, krypton, xenon, radon etc. The total volume of air present in atmosphere consists of 78 part nitrogen, 21 part oxygen and remaining 1 part other gases.

     Air is the mixture of________.

(a) Gases

(b) Solids

(c) Water  

(d) Soft drinks

Answer: (a)

Explanation

Air is the mixture of gases. Therefore, option (A) is correct and rest of the options is incorrect.

      Which one of the following is not a part of air?

(a) Argon

(b) Orange

(c) Nitrogen  

(d) Carbon dioxide

Answer: (b)

Explanation

Orange is a fruit. Hence, this is not a part of the air. Therefore, option (B) is correct and rest of the options is incorrect.