Chapter 3, Problem 91A

Interpretation Introduction

Interpretation:

Whether air is a solution or heterogeneous mixture and the technique used to separate air into its components needs to be determined.

Concept introduction:

Heterogeneous mixtures are the one that contain different components in two or more than two phases. Two immiscible liquids are also heterogeneous mixture.

Distillation is the process that is used to separate different components based on their boiling points. The components with lower boiling points leaves the vessel first continued with the rest.

Answer to Problem 91A

Air is a heterogeneous mixture.

Distillation is a process of purifying a liquid by heating or cooling it. This method is extensively used to separate the different components of air.

Explanation of Solution

Air is known to be a heterogeneous mixture rather than a solution as all the components that constitutes air are of different phases. Example:

Gaseous: ${\mathrm{N}}_2,O_2,C{O}_2,H_2,Ar,etc.$

Solid: dust particles

Liquid: water droplets, moisture, mist, etc.

Air is a mixture of gases consisting majorly nitrogen, oxygen and the inert gas argon. The remaining consists of carbon dioxide and the other inert rare gases. To separate them distillation process is used widely known as Air Separation Plants that uses thermal process to separate the different gases from one another to produce all the pure gases present in air.

Steps taken in separating air:

1. Compression of air
2. Pre-cooling the air
3. Purifying the air
4. Cooling
5. Separation
6. Withdrawal and storage.

Conclusion

Air is a heterogeneous mixture as it is made up of different phase components.

Air can be separated by number of ways out of which Distillation process is the easiest and most widely practiced.