Which of the following process is not in-built in the atmosphere to clean itself? Dispersion Flocculation Absorption Coalification

The process that is not in-built in the atmosphere to clean itself among the options provided is Coalification.

Here's why:

1. Dispersion: This is a natural process where pollutants are spread out and diluted by wind and weather patterns, reducing their concentration.

2. Flocculation: This is a process where particles in the atmosphere can clump together, often making them larger and heavier so they fall to the ground. This can help remove certain types of pollutants from the air.

3. Absorption: This is a process where gases or particles in the atmosphere are absorbed by other materials. For example, carbon dioxide is absorbed by trees and other plants in a process called photosynthesis.

4. Coalification: This is the process of transformation of plant debris into coal under conditions of high pressure and low temperature over millions of years. This is not a process that cleans the atmosphere. In fact, the burning of coal releases pollutants into the atmosphere.