Answer:

Sedimentation is the process in which sediments (gravel, pebbles etc.) settle down. This happens when we leave the solution untouched for a few hours. Since these sediments are heavier than the liquid, they settle down. The process of sedimentation can be speeded up by adding a small piece of alum to the solution.

Decantation takes place after the process of sedimentation. In this process, after the sediments have settled down, the above clear liquid has to be poured into another container making sure that the sediments do not come along with it.

Explanation:

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