For purifying drinking water alum is used

A. for coagulation of mud particles

B. to remove gases

C. to kill bacteria

D. to remove salts

Answer: Option A

Solution(By Examveda Team)

For purifying drinking water alum is used for coagulation of mud particles. Aluminium Sulfate, Shortly known as Alum, when added to raw water reacts with the bicarbonate alkalinities present in water and forms a gelatinous precipitate. The water over this sediment is almost clean other than some fine particles dissolved in it.