Civil Engineering - UPSC Civil Service Exam Questions - Discussion

Discussion Forum : UPSC Civil Service Exam Questions - Section 13 (Q.No. 39)

UPSC Civil Service Exam Questions

39.

Which of the following are associated with alum coagulation ?
1. A decrease of alkalinity in treated water
2. Formation of hydroxide flocs of aluminium
3. A slight decrease of pH in treated water
4. An increase of permanent hardness
Select the correct answer using the codes given below :

1, 2 and 3

1, 3 and 4

1, 2, 3 and 4

2 and 4