Why is alum added to water containing suspended impurities?

Question

Why is alum added to water containing suspended impurities? (A) To make a colloidal solution (B) To coagulate the suspended impurities (C) To remove impurities of calcium and magnesium (D) To protect the colloidal solution from getting precipitated

Tardigrade Admin · Accepted Answer

The water obtained from natural sources often contains suspended impurities. Alum is added to such water to coagulate the suspended impurities and make water fit for drinking purposes.

Q. Why is alum added to water containing suspended impurities?

To make a colloidal solution

To coagulate the suspended impurities

To remove impurities of calcium and magnesium

To protect the colloidal solution from getting precipitated

The water obtained from natural sources often contains suspended impurities. Alum is added to such water to coagulate the suspended impurities and make water fit for drinking purposes.