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This section includes 112 Mcqs, each offering curated multiple-choice questions to sharpen your Environmental Engineering knowledge and support exam preparation. Choose a topic below to get started.
51. |
The detention period of a lime soda treatment plant is ____________ |
A. | 1hour |
B. | 3hours |
C. | 2-4hours |
D. | 4-7hours |
Answer» D. 4-7hours | |
52. |
By which process, odour producing substances is oxidized? |
A. | Chlorination |
B. | Liming |
C. | Re-carbonation |
D. | Super-chlorination |
Answer» E. | |
53. |
Which of the following is a carbonaceous material? |
A. | Charcoal |
B. | Petroleum |
C. | Hydrogen sulfide |
D. | Sodium chloride |
Answer» B. Petroleum | |
54. |
The Total hardness of soft water as CaCO₃ equivalent is __________ |
A. | 50ppm |
B. | 100ppm |
C. | 150ppm |
D. | 200ppm |
Answer» B. 100ppm | |
55. |
The total hardness of water is 100ppm as CaCO₃ equivalent. What is the type of water? |
A. | Soft |
B. | Moderately hard |
C. | Hard |
D. | Very hard |
Answer» C. Hard | |
56. |
Which of the following is a disadvantage of the zeolite process? |
A. | No sludge is formed |
B. | The process is almost automatic |
C. | Suspended impurities get deposited around the zeolite particles |
D. | Zero hardness can be occurred |
Answer» D. Zero hardness can be occurred | |
57. |
Which of the following method is not used for desalination? |
A. | Distillation |
B. | Coagulation |
C. | Reverse osmosis |
D. | Freezing |
Answer» B. Coagulation | |
58. |
The dose of activated carbon in powdered form is controlled by ____________ |
A. | Chromatography |
B. | Distillation |
C. | Threshold odor test |
D. | MPN test |
Answer» D. MPN test | |
59. |
The process in which the brackish water is forced across a permeable membrane by mechanical forces is called as _____________ |
A. | Filtration |
B. | Semi filtration |
C. | Coagulation |
D. | Hyper filtration |
Answer» E. | |
60. |
The taste produced by a microorganism, can be controlled by ____________ |
A. | Potassium per-manganate |
B. | Potassium dichromate |
C. | Sodium chloride |
D. | Iodine |
Answer» B. Potassium dichromate | |
61. |
The temporary hardness in water is due to the presence of __________ |
A. | Sulfates, Chlorides |
B. | Sulfates, Chlorides, nitrates |
C. | Carbonates and bicarbonates |
D. | Sulfates and carbonates |
Answer» D. Sulfates and carbonates | |
62. |
What happens when water contains 8-20 ppm of fluoride concentration? |
A. | Blue baby disease |
B. | Crippling fluorosis |
C. | Dental fluorosis |
D. | Mottling of teeth |
Answer» C. Dental fluorosis | |
63. |
The reduction of carbon dioxide by cascade aerators is in the range of __________ |
A. | 10-20% |
B. | 20-30% |
C. | 40-50% |
D. | 50-60% |
Answer» E. | |
64. |
Which of the following is not used as a fluoride compound? |
A. | Sodium fluoride |
B. | Sodium silico fluoride |
C. | Hydrofluosilicic acid |
D. | Sodium fluro carbonate |
Answer» E. | |
65. |
The minimum reaction time allowed in the recarbonation basin is ____________ |
A. | 5minutes |
B. | 10minutes |
C. | 15minutes |
D. | 20minutes |
Answer» E. | |
66. |
Which of the following is not used for removing the permanent hardness? |
A. | Lime soda process |
B. | Zeolite process |
C. | Demineralization |
D. | Adding lime |
Answer» E. | |
67. |
Dealkalization results in removal of all the ions from the water. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
68. |
The coarse screen is inclined at _____ to facilitate the cleaning or raking. |
A. | 300 |
B. | 350 |
C. | 450 |
D. | 900 |
Answer» D. 900 | |
69. |
The permanent hardness is also known as __________ |
A. | Pseudo hardness |
B. | Non carbonate hardness |
C. | Carbonate hardness |
D. | Brinell hardness |
Answer» C. Carbonate hardness | |
70. |
The elapsed time in gravity filter is 1sec. What is the height of fall in a single descent? |
A. | 4.4m |
B. | 4.9m |
C. | 8.8m |
D. | 9.8m |
Answer» C. 8.8m | |
71. |
For removal of manganese from water ________ mg of oxygen is required. |
A. | 0.14 |
B. | 0.50 |
C. | 0.29 |
D. | 0.90 |
Answer» D. 0.90 | |
72. |
As far as safer handling is considered, which of the following is used for fluoridation? |
A. | Sodium fluoride |
B. | Sodium silico fluoride |
C. | Hydrofluosilicic acid |
D. | Sodium fluro carbonate |
Answer» D. Sodium fluro carbonate | |
73. |
Which of the following is the pure compound? |
A. | Sodium fluoride |
B. | Sodium silico fluoride |
C. | Hydrofluosilicic acid |
D. | Sodium fluro carbonate |
Answer» B. Sodium silico fluoride | |
74. |
Multistage flash evaporator produces _____ kg of water per kg of prime steam. |
A. | 5 |
B. | 10 |
C. | 15 |
D. | 20 |
Answer» E. | |
75. |
The time required for the mixing of lime and soda in lime soda process is _____________ |
A. | 10min |
B. | 20min |
C. | 40min |
D. | 80 min |
Answer» D. 80 min | |
76. |
Fluorides in solution form are preferred over powdered form for fluoridation. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
77. |
What is the dose of copper sulfate required for the treatment of water? |
A. | 0.3-0.6ppm |
B. | 2-6ppm |
C. | 4-8ppm |
D. | 10-20ppm |
Answer» B. 2-6ppm | |
78. |
Activated carbon in powder form is applied in the mixing basin. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» B. False | |
79. |
The process of reducing the fluoride content from water is called _____ |
A. | Chlorination |
B. | Fluoridation |
C. | Defluoridation |
D. | Flocculation |
Answer» D. Flocculation | |
80. |
In which process of water softening, ion exchange phenomenon takes place? |
A. | Lime soda process |
B. | Zeolite process |
C. | Boiling |
D. | Demineralization process |
Answer» C. Boiling | |
81. |
Removal of iron from water takes place at a pH of ______ |
A. | 1.5 |
B. | 3 |
C. | 8.2 |
D. | 9.4 |
Answer» E. | |
82. |
The color of the natural zeolite is ____________ |
A. | Green |
B. | Grey |
C. | Black |
D. | Blue |
Answer» B. Grey | |
83. |
The permanent hardness in water is due to the presence of __________ |
A. | Sulfates, Chlorides |
B. | Sulfates, chlorides, nitrates |
C. | Carbonates and bicarbonates |
D. | Sulfates and carbonates |
Answer» C. Carbonates and bicarbonates | |
84. |
Due to the Aswan dam in Egypt, the countries cultivated area has been increased to |
A. | 4-8 % |
B. | 3-5% |
C. | 4-7% |
D. | 2-5% |
Answer» B. 3-5% | |
85. |
There are protozoa present in the water. Its name is Dinobryen. What is the dose of copper sulfate required to kill it? |
A. | 0.02ppm |
B. | 0.3ppm |
C. | 0.5ppm |
D. | 0.8ppm |
Answer» C. 0.5ppm | |
86. |
Which organism is the carrier of sleeping sickness disease? |
A. | Snail |
B. | Tsetse Fly |
C. | Guinea worm |
D. | Fly |
Answer» C. Guinea worm | |
87. |
Which chemical is used for removing the permanent hardness of Calcium chloride? |
A. | Lime |
B. | Chlorine |
C. | Soda |
D. | Both lime and soda |
Answer» C. Soda | |
88. |
In which desalination process, the salt ions are removed from seawater by means of electric current? |
A. | Distillation |
B. | Electro-dialysis |
C. | Reverse osmosis |
D. | Freezing |
Answer» C. Reverse osmosis | |
89. |
The brown tinge in the water is due to the presence of ____________ |
A. | Zinc |
B. | Copper |
C. | Iron |
D. | Manganese |
Answer» E. | |
90. |
The maximum salt concentration up to which desalination of brackish water is possible by Electro-dialysis is _____________ |
A. | 1000ppm |
B. | 2000ppm |
C. | 3000ppm |
D. | 5000ppm |
Answer» E. | |
91. |
The solar evaporation can yield about ___ kg of fresh water per day per m² of basin surface. |
A. | 5 |
B. | 10 |
C. | 15 |
D. | 20 |
Answer» B. 10 | |
92. |
Which of the following regarding ozonation is incorrect? |
A. | Improves the appearance of water |
B. | Removes traces of color |
C. | Remove odor |
D. | Remove phenolic and algae taste |
Answer» E. | |
93. |
Fluorex is a special mixture of ____________ |
A. | Di-calcium phosphate and carbon |
B. | Tri-calcium phosphate and hydroxyapatite |
C. | Di-calcium phosphate and phosphoric acid |
D. | Tri-calcium phosphate and carbon |
Answer» C. Di-calcium phosphate and phosphoric acid | |
94. |
The zeolite process is unsuitable for water containing iron and manganese. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» B. False | |
95. |
Iron and Manganese are generally present in water supplies as ____________ |
A. | Suspension |
B. | Solution |
C. | Colloidal particles |
D. | Either suspension or solution |
Answer» E. | |
96. |
By which process dissolved manganese compounds can be converted into insoluble manganese compounds? |
A. | Aeration |
B. | Coagulation |
C. | Sedimentation |
D. | Flocculation |
Answer» B. Coagulation | |
97. |
In which process, excess lime is converted into bicarbonate? |
A. | Chlorination |
B. | Liming |
C. | Re-carbonation |
D. | Super-chlorination |
Answer» D. Super-chlorination | |
98. |
Micro strainers are used to remove color in water. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
99. |
Granular activated carbon has a surface area of ____________ |
A. | 100-200m²/g |
B. | 500-1400m²/g |
C. | 400-600m²/g |
D. | 500-900m²/g |
Answer» C. 400-600m²/g | |
100. |
Which material is used in contact filters for the removal of fluorides? |
A. | Calcium phosphate |
B. | Copper sulfate |
C. | Synthetic tri-calcium phosphate |
D. | Bone charcoal |
Answer» D. Bone charcoal | |