Chapter 20, Problem 1PS

Interpretation Introduction

Interpretation:

The atmospheric gas which is present in highest concentration in dry air should be determined from the given gases.

Concept introduction:

Earth’s Atmosphere:  It is the layer of gases that surrounds the planet earth and is retained by Earth’s gravity.

Dry air is air that has low relative humidity and no water vapor.

Answer to Problem 1PS

The gas present in highest concentration in dry air is Option (b) ${\text{CH}}_{\text{4}}$

Explanation of Solution

Reason for the correct answer:

In atmosphere there are different types of air in different concentration are present.

Concentration of air may be changed in accordance with the temperature variation in the air. In dry air methane ${\text{CH}}_{\text{4}}$ has highest concentration.

Reason for the incorrect options:

In dry air methane has the highest concentration therefore the other given options such as,

(a) $N_{2}O$

(c) $O_3$

(d)  $CO$

are incorrect. 

Conclusion

The gas present in highest concentration in dry air is methane.