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This section includes 182 Mcqs, each offering curated multiple-choice questions to sharpen your Civil Engineering knowledge and support exam preparation. Choose a topic below to get started.
51. |
The aeration system will decrease the redox potential of the water. |
A. | true |
B. | false |
Answer» C. | |
52. |
What is the tank volume of aeration for water flow of 50m3/h? |
A. | 40 m3 |
B. | 50 m3 |
C. | 80 m3 d) 100 m3 |
Answer» C. 80 m3 d) 100 m3 | |
53. |
What is the minimum time of aeration? |
A. | 20 minutes |
B. | 40 minutes |
C. | 60 minutes |
D. | 80 minutes |
Answer» D. 80 minutes | |
54. |
At what pH should the water be maintained? |
A. | 6.5 |
B. | 7.5 |
C. | 8.5 |
D. | 9 |
Answer» C. 8.5 | |
55. |
What is the permitted concentration of arsenic in drinking water? |
A. | 10 g/l |
B. | 20 g/l |
C. | 30 g/l |
D. | 40 g/l |
Answer» B. 20 g/l | |
56. |
What is the permitted concentration of manganese in drinking water? |
A. | 30 g/l |
B. | 40 g/l |
C. | 50 g/l |
D. | 60 g/l |
Answer» D. 60 g/l | |
57. |
For obtaining Silica<5 ppm which of these should be utilized? |
A. | sba followed by mixed be |
B. | sba |
C. | wba sba followed by mixed bed |
D. | mixed bed |
Answer» B. sba | |
58. |
What is the preferred regenerant in case of anion exchanger? |
A. | nacl |
B. | naoh |
C. | na2so4 |
D. | na2co3 |
Answer» C. na2so4 | |
59. |
In which year was the Ferrosand process patented? |
A. | 1960 |
B. | 1965 |
C. | 1970 |
D. | 1975 |
Answer» C. 1970 | |
60. |
In case along with silica, there is high content in sulphide and chloride what should be used? |
A. | wba |
B. | wba and sba |
C. | sba |
D. | sba,wba and wac |
Answer» C. sba | |
61. |
What is the preferred regenerant in case of cation exchanger? |
A. | hcl |
B. | h2so4 |
C. | h2co3 |
D. | hf |
Answer» B. h2so4 | |
62. |
When the hardness and alkalinity are around 30% what should be used? |
A. | sac |
B. | wac |
C. | wac, sac |
D. | wac, sac, wba |
Answer» D. wac, sac, wba | |
63. |
When is strong basic anion not necessary? |
A. | silica is nil |
B. | co2 is nil |
C. | fluroine is nil |
D. | sulphate is nil |
Answer» B. co2 is nil | |
64. |
While designing the demineralisation plant what is considered as the weak basic anion load? |
A. | alkaline hardness |
B. | alkaline hardness + ema |
C. | ema |
D. | silica |
Answer» D. silica | |
65. |
While designing the demineralisation plant what is considered as the strong basic anion load? |
A. | alkaline hardness |
B. | alkaline hardness + ema+co2 |
C. | ema+silica |
D. | silica+co2+ alkalinity+ema |
Answer» E. | |
66. |
While designing the demineralisation plant what is considered as the strong acidic cation load? |
A. | alkaline hardness |
B. | alkaline hardness + ema |
C. | ema |
D. | silica |
Answer» C. ema | |
67. |
While designing the demineralisation plant what is considered as the weak acidic cation load? |
A. | alkaline hardness |
B. | alkaline hardness+ ema |
C. | ema |
D. | silica |
Answer» B. alkaline hardness+ ema | |
68. |
Which of these have a negative electrical charge? |
A. | calcium |
B. | magnesium |
C. | sodium |
D. | chloride |
Answer» E. | |
69. |
The ions with opposite charge can be exchanged. |
A. | true |
B. | false |
Answer» C. | |
70. |
Ion exchange units are known as |
A. | water hardeners |
B. | water softeners |
C. | water purifiers |
D. | exchangers |
Answer» C. water purifiers | |
71. |
Water softener units work most efficiently with particulate water. |
A. | true |
B. | false |
Answer» C. | |
72. |
In which type of tube settler, tubes are slightly inclined in the direction of normal flow? |
A. | solid contact clarifier |
B. | steeply inclined tube settler |
C. | vertical tube settler |
D. | horizontal tube settler |
Answer» E. | |
73. |
Which device solved the problem of unstable hydraulic conditions and operation of sludge removal equipment? |
A. | centrifugal pump |
B. | pulsator clarifier |
C. | tube settler |
D. | flocculator |
Answer» D. flocculator | |
74. |
In which device, the primary mixing is followed by a secondary reaction zone resulting in formation of sludge blanket? |
A. | centrifugal pump |
B. | flocculator |
C. | tube settler |
D. | solid contact clarifier |
Answer» E. | |
75. |
The pulsator clarifier is a type of |
A. | horizontal flow sludge tank |
B. | vertical flow sludge tank |
C. | circular sludge tank |
D. | plain sedimentation tank |
Answer» C. circular sludge tank | |
76. |
What is the detention period of a clarifier used in the treatment of water? |
A. | 1hour |
B. | 2hours |
C. | 3hours |
D. | 4hours |
Answer» D. 4hours | |
77. |
The design value of the velocity of flow in a flocculator is |
A. | 0.2-0.8m/s |
B. | 0.3-0.5m/s |
C. | 0.6-0.8m/s |
D. | 0.1-0.5m/s |
Answer» B. 0.3-0.5m/s | |
78. |
What is the normal value of the detention period adopted in a flocculator for design purpose? |
A. | 30min |
B. | 60min |
C. | 90min |
D. | 100min |
Answer» B. 60min | |
79. |
What is the dimension formula of mean velocity gradient? |
A. | 1/t |
B. | 1/t2 |
C. | t |
D. | t2 |
Answer» B. 1/t2 | |
80. |
                     is an operation designed to force agitation in the fluid and induce coagulation. |
A. | sedimentation |
B. | flocculation |
C. | disinfection |
D. | aeration |
Answer» C. disinfection | |
81. |
Organic contaminants are removed from the water by the process of |
A. | water softening |
B. | demineralization |
C. | absorption |
D. | adsorption |
Answer» E. | |
82. |
Dealkalization results in removal of all the ions from the water. |
A. | true |
B. | false |
Answer» C. | |
83. |
Solids are removed from the water by which of the following unit operation? |
A. | inter facial contact |
B. | solid stabilization |
C. | ion transfer |
D. | solids transfer |
Answer» E. | |
84. |
By which process, odour producing substances is oxidized? |
A. | chlorination |
B. | liming |
C. | re-carbonation |
D. | super-chlorination |
Answer» E. | |
85. |
In which process, excess lime is converted into bicarbonate? |
A. | chlorination |
B. | liming |
C. | re-carbonation |
D. | super-chlorination |
Answer» D. super-chlorination | |
86. |
Which form of solute stabilization occurs when water passes through limestone? |
A. | chlorination |
B. | liming |
C. | re-carbonation |
D. | super-chlorination |
Answer» C. re-carbonation | |
87. |
In which form of solute stabilization, hydrogen sulfide in water is oxidized into sulfate? |
A. | chlorination |
B. | liming |
C. | re-carbonation |
D. | super-chlorination |
Answer» B. liming | |
88. |
In which unit operation objectionable solutes are converted into unobjectionable forms without removal? |
A. | gas transfer |
B. | ion transfer |
C. | solute stabilization |
D. | solids transfer |
Answer» D. solids transfer | |
89. |
Flocculation of iron from water by the addition of lime is an example of which of the following process? |
A. | chemical precipitation |
B. | chemical coagulation |
C. | ion exchange |
D. | adsorption |
Answer» B. chemical coagulation | |
90. |
Which of the following process is used to remove the colloidal particles from water? |
A. | chemical precipitation |
B. | chemical coagulation |
C. | ion exchange |
D. | adsorption |
Answer» C. ion exchange | |
91. |
How many types of aerators are commonly used in the treatment of water? |
A. | 2 |
B. | 3 |
C. | 4 |
D. | 5 |
Answer» D. 5 | |
92. |
In which unit operation, gases are released or absorbed in the water? |
A. | gas transfer |
B. | ion transfer |
C. | solute stabilization |
D. | solids transfer |
Answer» B. ion transfer | |
93. |
Which type of pump is used while handling the sludge disposal system? |
A. | screw pump |
B. | multistage pump |
C. | self-priming pump |
D. | vertical pump |
Answer» B. multistage pump | |
94. |
In an activated sludge process which type of pump is used to recirculate the sludge? |
A. | booster pump |
B. | centrifugal pump |
C. | vane pump |
D. | vertical turbine pump |
Answer» C. vane pump | |
95. |
Which type of pump should be selected in order to pump the sewage from a septic tank to the water treatment system? |
A. | vertical sump pump |
B. | progressive cavity pump |
C. | submersible pump |
D. | screw pump |
Answer» D. screw pump | |
96. |
Which type of pump should be used in order to handle low viscosity fluids? |
A. | centrifugal pump |
B. | displacement pump |
C. | submersible pump |
D. | end suction pump |
Answer» B. displacement pump | |
97. |
Which pump among the ones mentioned below can be located above the suction reservoir without an external priming system? |
A. | slurry pumps |
B. | self-priming pumps |
C. | submersible pumps |
D. | trash pumps |
Answer» C. submersible pumps | |
98. |
End suction pumps are the common type of                    pumps. |
A. | drum pumps |
B. | centrifugal pumps |
C. | positive displacement pumps |
D. | grinder pumps |
Answer» C. positive displacement pumps | |
99. |
Which type of pump is designed to handle rocks and other solids? |
A. | trash pumps |
B. | submersible pumps |
C. | slurry pumps |
D. | self-priming pumps |
Answer» B. submersible pumps | |
100. |
Why are cryogenic pumps used? |
A. | boost pressure |
B. | handle low temperature liquids |
C. | handle high temperature liquids |
D. | pump small quantities of liquids |
Answer» C. handle high temperature liquids | |