Which one of the following is used in the purification of drinking water?
A. silver sol protected by gelatine
B. milk of magnesia
C. Alum containing Al3+
D. Argyrol
Answer:C
Which one of the following is used in the purification of drinking water?
A. silver sol protected by gelatine B. milk of magnesia C. Alum containing Al3+ D. Argyrol