Answer:
It prevent the solution from making 100% pure alum.
Step-by-step explanation:
Large chunks could be bad if we make 100% pure alum because the large chunks prevent the production of 100% pure alum so for making 100% pure alum, large chunks will be removed from the solution or process. Alum is a chemical compound having salt of sulfate attached with aluminum in hydrated form i. e. presence of water. It is widely used in vaccines and for the purification of drinking water.