A. Ferrous sulphate
B. Alum
C. Lime
D. Hydrazine
A. Coal
B. Silica
C. Iron
D. None of these
A. Foul smell and taste
B. Iron and manganese
C. Temporary hardness
D. Permanent hardness
A. Natural aeration of water stream
B. Photosynthetic action of algae
C. Both A. & B.
D. Neither A. nor B.
A. Lagooning
B. Activated carbon adsorption
C. Biological oxidation pond
D. Chemical coagulation
A. Diameter
B. Inlet gas velocity
C. Overall height
D. All A., B. & C.
A. Evaporation & chemical precipitation
B. Biological methods & adsorption in ion exchange materials
C. Fixing into a solid mass with cement and sinking deep in the sea
D. All A., B. & C.