Question

Alum is used in the purification of river water. Give reasons.

Answer 1

• Alum is used to make water purify because it is a recyclable thing, which can be used to make the water clean as it absorbs all the impurities and settle them down.
• The heavy particles of dissolved alum deposit on the suspended clay particles in water and settles down at the bottom.

Hence, alum is used in the purification of river water.