A. Before
B. After
C. During
D. To avoid
Related Mcqs:
- The most widely used coagulant for removing suspended impurities from water is__________________?
A. Bleaching powder
B. Chlorine
C. Calcium sulphate
D. Alum - Alum [Al2(SO4)3] is used as a coagulant in water treatment to remove____________________?
A. Colour
B. Turbidity
C. Bacteria
D. All A , B. and C. - Which of the following is used as a coagulant in water treatment ?
A. Chloramine
B. Chlorine
C. Ferrous sulphate
D. Hydrogen peroxide - Which of the following is used as a coagulant in treating turbid water ?
A. Chlorine
B. Ferric sulphate
C. Calcium sulphate
D. Activated carbon - Most widely and commonly used coagulant for the removal of suspended impurities in water is __________________?
A. Bleaching powder
B. Slaked lime
C. Alum
D. Copper sulphate - Extraction of _________________ employs an electrolytic process ?
A. Aluminium
B. Silver
C. Copper
D. All A, B. and C - Soap cannot be used with hard water, because _________________?
A. Hard water contains sulphate
B. They form insoluble calcium soaps which precipitate
C. They attract back the removed dirt
D. None of these - Na2CO3 is called _________________?
A. Washing soda
B. Soda ash
C. Plaster of Paris
D. Calcite - _________________ is not a constituent of gun powder?
A. Carbon
B. Charcoal
C. Sulphur
D. Potassium nitrate - Washing soda is chemically represented by _________________?
A. Na2CO3
B. Na2CO3.H2O
C. Na2CO3.10H2O
D. NaHCO3
