Question

a crystal of alum is used for cleaning muddy water​

Answer 1

answer-

Aluminium Sulfate, Shortly known as Alum, when added to raw water reacts with the bicarbonate alkalinities present in water and forms a gelatinous precipitate. This floc attracts other fine particles and suspended material in raw water, and settles down at the bottom of the container.this is how alum is used to clean water

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