McqMate
| 101. |
Which of the following option is incorrect about the sludges? |
| A. | Sludges are soft, loose and slimy precipitate |
| B. | They are non-adherent deposits and can be easily removed |
| C. | Formed generally at heated portions of the boiler |
| D. | Can be removed by blow down operation |
| Answer» C. Formed generally at heated portions of the boiler | |
| 102. |
The propulsion of water into steam drum by extremely rapid, almost explosive boiling of water at the heating surface is called ___________ |
| A. | Foaming |
| B. | Priming |
| C. | Corrosion |
| D. | Caustic embrittlement |
| Answer» B. Priming | |
| 103. |
The phenomenon during which the boiler material becomes brittle due to accumulation of caustic substances is known as ___________ |
| A. | Foaming |
| B. | Priming |
| C. | Corrosion |
| D. | Caustic embrittlement |
| Answer» D. Caustic embrittlement | |
| 104. |
Foaming is caused by the formation of ___________ |
| A. | Acids |
| B. | Alcohols |
| C. | Oils and alkalis |
| D. | Ketones |
| Answer» C. Oils and alkalis | |
| 105. |
The term ‘Sullage’ refers to: |
| A. | Fresh wastewater |
| B. | Septic wastewater |
| C. | Wastewater from kitchen, laundry |
| D. | Toxic wastewater |
| Answer» C. Wastewater from kitchen, laundry | |
| 106. |
Wastewater can become septic by the loss of: |
| A. | Dissolved oxygen content |
| B. | Carbon content |
| C. | Organic compounds |
| D. | Water content |
| Answer» A. Dissolved oxygen content | |
| 107. |
Which one of the below is not an attribute of drinking water? |
| A. | Aesthetics |
| B. | Economic |
| C. | Safety |
| D. | Source |
| Answer» D. Source | |
| 108. |
The extent of water treatment depends on how many factors? |
| A. | 5 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» B. 2 | |
| 109. |
What is added to the water treatment tank to settle the colloidal particles? |
| A. | Alum |
| B. | Alum and lime |
| C. | Lime |
| D. | Potash |
| Answer» B. Alum and lime | |
| 110. |
Disinfection of water in our country is mainly done by ____________ |
| A. | Oxygenation |
| B. | Hydration |
| C. | Chlorination |
| D. | Filtration |
| Answer» C. Chlorination | |
| 111. |
Which minerals and in what form are present in ground water? |
| A. | Fe & Mn in Ferrous and Manganous |
| B. | Fe & Cu in Ferric and Cupric |
| C. | Fe & Mn in Ferric and manganous |
| D. | Cu & Mn in Cuprous and manganous |
| Answer» A. Fe & Mn in Ferrous and Manganous | |
| 112. |
How many types of wastewater treatment plants are there based on the type of wastewater? |
| A. | 5 |
| B. | 4 |
| C. | 2 |
| D. | 3 |
| Answer» D. 3 | |
| 113. |
On how many conditions does the intervention of wastewater depend on? |
| A. | 5 |
| B. | 7 |
| C. | 6 |
| D. | 4 |
| Answer» B. 7 | |
| 114. |
The surface water quality is affected by _______ and infiltration from rainfall. |
| A. | Precipitation |
| B. | Run off |
| C. | Wetlands |
| D. | Farming |
| Answer» B. Run off | |
| 115. |
_________ are constructed for water supply, electricity generation, recreation, irrigation and others. |
| A. | Swimming pools |
| B. | Ponds |
| C. | Reservoirs |
| D. | Tanks |
| Answer» C. Reservoirs | |
| 116. |
What is the next step after water abstraction in wastewater treatment? |
| A. | Supply to consumers |
| B. | Treatment |
| C. | Combine with stormwater |
| D. | Supply to receiving body |
| Answer» B. Treatment | |
| 117. |
Which of the following requires aesthetically pleasant water? |
| A. | Domestic use |
| B. | Industrial use |
| C. | Irrigation |
| D. | Aquaculture |
| Answer» B. Industrial use | |
| 118. |
The addition of substances or energy forms that directly or indirectly alter the nature of the water body is called? |
| A. | Water contamination |
| B. | Water pollution |
| C. | Sanitation |
| D. | Water treatment |
| Answer» B. Water pollution | |
| 119. |
What is the type of pollution where the pollutants reach the water body in points called? |
| A. | Point-source pollution |
| B. | Diffuse pollution |
| C. | Point-source contamination |
| D. | Diffuse contamination |
| Answer» A. Point-source pollution | |
| 120. |
What percentage of solids does wastewater contain? |
| A. | 0.5% |
| B. | 5% |
| C. | 0.1% |
| D. | 1% |
| Answer» C. 0.1% | |
| 121. |
What is the growth of huge amounts of algae and other aquatic plants leading to the deterioration of the water quality called? |
| A. | Eutrophication |
| B. | Algae growth |
| C. | Nitrification |
| D. | Denitrification |
| Answer» A. Eutrophication | |
| 122. |
The optimum temperature for bacterial activity is in what range? |
| A. | 25-35 degree Celsius |
| B. | 50 degree Celsius |
| C. | 20 degree Celsius |
| D. | 40 degree Celsius |
| Answer» A. 25-35 degree Celsius | |
| 123. |
The fluoride concentration for prevention of dental caries is ____________ |
| A. | 1mg/l |
| B. | 2mg/l |
| C. | 3mg/l |
| D. | 4mg/l |
| Answer» A. 1mg/l | |
| 124. |
In which process, the fluoride content of water is raised? |
| A. | Chlorination |
| B. | Fluoridation |
| C. | Defluoridation |
| D. | Flocculation |
| Answer» B. Fluoridation | |
| 125. |
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» D. Sodium fluro carbonate | |
| 126. |
Which of the following is the pure compound? |
| A. | Sodium fluoride |
| B. | Sodium silico fluoride |
| C. | Hydrofluosilicic acid |
| D. | Sodium fluro carbonate |
| Answer» A. Sodium fluoride | |
| 127. |
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» C. Hydrofluosilicic acid | |
| 128. |
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» B. Crippling fluorosis | |
| 129. |
The process of reducing the fluoride content from water is called _____ |
| A. | Chlorination |
| B. | Fluoridation |
| C. | Defluoridation |
| D. | Flocculation |
| Answer» C. Defluoridation | |
| 130. |
Which of the following is not used for defluoridation? |
| A. | Calcium phosphate |
| B. | Copper sulfate |
| C. | Alum |
| D. | Bone charcoal |
| Answer» B. Copper sulfate | |
| 131. |
At which temperature, the bone is calcinated during defluoridation with calcium phosphate? |
| A. | 100-200oC |
| B. | 200-300oC |
| C. | 400-600oC |
| D. | 500-800oC |
| Answer» C. 400-600oC | |
| 132. |
One cubic metre of bone can treat how much quantity of water containing 3.5 ppm of fluoride? |
| A. | 10m3 |
| B. | 100m3 |
| C. | 1000m3 |
| D. | 10000m3 |
| Answer» B. 100m3 | |
| 133. |
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» C. Synthetic tri-calcium phosphate | |
| 134. |
Which material is used for removing fluorides from hard water containing 3ppm of fluorides? |
| A. | Lime |
| B. | Copper sulfate |
| C. | Synthetic tri-calcium phosphate |
| D. | Bone charcoal |
| Answer» A. Lime | |
| 135. |
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» B. Tri-calcium phosphate and hydroxyapatite | |
| 136. |
Which of these materials is not added to iron for improving its oxidation resistance? |
| A. | Nickel |
| B. | Chromium |
| C. | Aluminum |
| D. | Silicon |
| Answer» D. Silicon | |
| 137. |
How much chromium is required to provide oxidation resistance for use over 1000oC? |
| A. | 1% |
| B. | 6% |
| C. | 12% |
| D. | 17% |
| Answer» D. 17% | |
| 138. |
Molybdenum with hydrogen can be used up to ________ |
| A. | 1000oC |
| B. | 1500oC |
| C. | 2000oC |
| D. | 4000oC |
| Answer» B. 1500oC | |
| 139. |
% chromium mixed with ______ can be used up to 1100oC. |
| A. | Nickel |
| B. | Chromium |
| C. | Aluminum |
| D. | Silicon |
| Answer» A. Nickel | |
| 140. |
Which of these metals does not require alloying for oxidation resistance? |
| A. | Iron |
| B. | Copper |
| C. | Aluminum |
| D. | Molybdenum |
| Answer» C. Aluminum | |
| 141. |
_________ is used to prevent duralumin from corrosion. |
| A. | Iron |
| B. | Kynal |
| C. | Titanium |
| D. | Alclad |
| Answer» D. Alclad | |
| 142. |
Galvanized ion is made by dipping low carbon steel in molten zinc at ________ |
| A. | 100oC |
| B. | 150oC |
| C. | 200oC |
| D. | 450oC |
| Answer» D. 450oC | |
| 143. |
Which of these is not a way to prevent intergranular corrosion? |
| A. | Reduction of carbon level |
| B. | Quenching |
| C. | Addition of carbide forming elements |
| D. | Reduction of alloying elements |
| Answer» D. Reduction of alloying elements | |
| 144. |
Dezincification of brass is prevented by addition of ________ |
| A. | Nickel |
| B. | Zinc |
| C. | Arsenic |
| D. | Tungsten |
| Answer» C. Arsenic | |
| 145. |
Season-cracking can be prevented by cold-working of brass at _________ |
| A. | 15oC |
| B. | 100oC |
| C. | 300oC |
| D. | 550oC |
| Answer» C. 300oC | |
| 146. |
How can caustic embrittlement be avoided? |
| A. | Addition of nickel |
| B. | Increasing potential |
| C. | Decreasing carbon |
| D. | Adding tannins |
| Answer» D. Adding tannins | |
| 147. |
A grit chamber is usually installed ______ primary sedimentation tanks. |
| A. | Before |
| B. | After |
| C. | In between |
| D. | In |
| Answer» A. Before | |
| 148. |
At what velocity will the particles settle down? |
| A. | 0.5 m/s |
| B. | 0.3 m/s |
| C. | 0.1 m/s |
| D. | 0.25 m/s |
| Answer» B. 0.3 m/s | |
| 149. |
Grit chambers are constructed to prevent their accumulation in _______ |
| A. | Sedimentation tank |
| B. | Sludge digesters |
| C. | Coagulation tank |
| D. | Sand filter |
| Answer» B. Sludge digesters | |
| 150. |
What is the cleaning period for manual grit chambers? |
| A. | 3 days |
| B. | 5 days |
| C. | 48 hours |
| D. | 1 week |
| Answer» D. 1 week | |
| 151. |
Grit chamber is similar to which of the following? |
| A. | Screening unit |
| B. | Sedimentation tank |
| C. | Coagulation tank |
| D. | Sand bed |
| Answer» B. Sedimentation tank | |
| 152. |
What is the specific gravity of settleable particles in the grit chamber? |
| A. | 2.98 |
| B. | 2.56 |
| C. | 2.65 |
| D. | 2.89 |
| Answer» C. 2.65 | |
| 153. |
Stoke’s law holds good for Reynolds’s number ______ |
| A. | Less than 1 |
| B. | Equal to 1 |
| C. | Greater than 1 |
| D. | Nearer to 1 |
| Answer» A. Less than 1 | |
| 154. |
What is the horizontal velocity considered for grit chamber? |
| A. | 0.25-0.4m/sec |
| B. | 0.6-0.9 m/sec |
| C. | 1-2 m/sec |
| D. | 3-4m/sec |
| Answer» A. 0.25-0.4m/sec | |
| 155. |
What is the detention time considered for aerated grit chamber? |
| A. | 5-6 mins |
| B. | 2-5 mins |
| C. | 1-2 mins |
| D. | 3-4 mins |
| Answer» B. 2-5 mins | |
| 156. |
Which of these is not a grit removal equipment installed in the aerated grit chamber? |
| A. | Screw conveyers |
| B. | Tubular conveyers |
| C. | Jet pumps |
| D. | Communitors |
| Answer» D. Communitors | |
| 157. |
What is the amount of air supplied for these grit chambers? |
| A. | 1-2 m3/m.min |
| B. | 0.2-0.5 m3/m.min |
| C. | 0.5-0.8 m3/m.min |
| D. | 0.8-1 m3/m.min |
| Answer» B. 0.2-0.5 m3/m.min | |
| 158. |
At what depth are the air diffusers placed in the grit chamber? |
| A. | 0.6-0.9 m |
| B. | 1-2 m |
| C. | 0.1-0.4m |
| D. | 0.45-0.6 m |
| Answer» D. 0.45-0.6 m | |
| 159. |
What is the amount of grit quantities captured by the aerated grit chamber? |
| A. | 0.004-0.20 m3/103.m3 |
| B. | 0.25 m3/103.m3 |
| C. | <0.004 m3/103.m3 |
| D. | 0.5 m3/103.m3 |
| Answer» A. 0.004-0.20 m3/103.m3 | |
| 160. |
Usually while designing what is the range of the width of the aerated grit chamber assumed? |
| A. | 0.5-2 m |
| B. | 8-10 m |
| C. | 2.5-7.0m |
| D. | 12m |
| Answer» C. 2.5-7.0m | |
| 161. |
Usually while designing what is the range of length of the aerated grit chamber assumed? |
| A. | 7.5-20 |
| B. | 4-6 m |
| C. | 25 m |
| D. | 50 m |
| Answer» A. 7.5-20 | |
| 162. |
Usually while designing what is the range of depth of the aerated grit chamber assumed? |
| A. | 0.5-2 m |
| B. | 8-10 m |
| C. | 2-5 m |
| D. | 12 m |
| Answer» C. 2-5 m | |
| 163. |
Aerated grit chambers are usually designed to remove particles in which range of size? |
| A. | 0.1mm diameter |
| B. | 0.35 mm diameter |
| C. | 0.21 mm diameter |
| D. | 0.41 mm diameter |
| Answer» C. 0.21 mm diameter | |
| 164. |
Activated sludge process degrade organics and _________ |
| A. | Improve nutrients |
| B. | Remove nutrients |
| C. | Remove odour |
| D. | Remove taste |
| Answer» B. Remove nutrients | |
| 165. |
What is required to keep the activated sludge suspended? |
| A. | Carbon-dioxide |
| B. | Nitrogen |
| C. | Oxygen |
| D. | Ammonia |
| Answer» C. Oxygen | |
| 166. |
What does the bacterium use to grow? |
| A. | Oxygen |
| B. | Organic pollutants |
| C. | Water |
| D. | Carbon-dioxide |
| Answer» B. Organic pollutants | |
| 167. |
________ combines aeration basin and secondary clarifier into single unit. |
| A. | Primary clarifier |
| B. | Aerobic unit |
| C. | Sequential batch reactor |
| D. | Secondary clarifier |
| Answer» C. Sequential batch reactor | |
| 168. |
What does SBR stand for? |
| A. | Secondary batch reactor |
| B. | Sequential biological reactor |
| C. | Secondary biological reactor |
| D. | Sequential batch reactor |
| Answer» D. Sequential batch reactor | |
| 169. |
SBR operates as ________ process. |
| A. | Batch |
| B. | Continuous |
| C. | Semi-continuous |
| D. | Discontinuous |
| Answer» A. Batch | |
| 170. |
When the aeration system shuts off, the basin begins to perform as a ______ |
| A. | Primary clarifier |
| B. | Secondary clarifier |
| C. | Anaerobic unit |
| D. | Aeration unit |
| Answer» B. Secondary clarifier | |
| 171. |
_______ provides the dual purpose of providing DO and mixing of the mixed liquor and wastewater. |
| A. | Flocculation |
| B. | Aeration |
| C. | Sedimentation |
| D. | Clarification |
| Answer» B. Aeration | |
| 172. |
Ion-exchange resin is ____________ |
| A. | Linear |
| B. | Low molecular weight |
| C. | Organic polymer with porous structure |
| D. | Soluble |
| Answer» C. Organic polymer with porous structure | |
| 173. |
Which of the following ion get released from the cation exchange column? |
| A. | H+ |
| B. | Na+ |
| C. | K+ |
| D. | Ca+2 |
| Answer» A. H+ | |
| 174. |
Which of the following ion get released from the anion exchange column? |
| A. | CO3-2 |
| B. | OH– |
| C. | Cl– |
| D. | SO4-2 |
| Answer» B. OH– | |
| 175. |
Ion-free water coming out from the exchanger is known as ____________ |
| A. | Potable water |
| B. | Disinfected water |
| C. | Coagulated water |
| D. | Demineralised water |
| Answer» D. Demineralised water | |
| 176. |
Which of the following statement is incorrect about the demineralised water? |
| A. | It is as pure as distilled water |
| B. | It is very good for use in high pressure boilers |
| C. | It is fit for domestic use |
| D. | It can be made either by distillation or by using cation and anion exchangers |
| Answer» C. It is fit for domestic use | |
| 177. |
The exhausted cation exchange column is regenerated by passing a solution of ____________ |
| A. | Dil. HCl |
| B. | Dil. NaCl |
| C. | Conc. HCl |
| D. | Conc. NaCl |
| Answer» A. Dil. HCl | |
| 178. |
The exhausted anion exchange column is regenerated by passing a solution of ____________ |
| A. | Dil. KOH |
| B. | Conc. KOH |
| C. | Conc. NaOH |
| D. | Dil. NaOH |
| Answer» D. Dil. NaOH | |
| 179. |
In ion-exchange process, the capital cost is _________ and the operational expenses are ______________ |
| A. | Low, high |
| B. | High, low |
| C. | High, high |
| D. | Low, low |
| Answer» C. High, high | |
| 180. |
The residual hardness in ion-exchange process is ____________ |
| A. | 0-2 ppm |
| B. | 5-10 ppm |
| C. | 10-15 ppm |
| D. | 20-30 ppm |
| Answer» A. 0-2 ppm | |
| 181. |
How many oxygen atoms are present in the ozone? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 182. |
_______ is produced by subjecting oxygen to high electric voltage. |
| A. | Carbon-monoxide |
| B. | Carbon-dioxide |
| C. | Pure oxygen |
| D. | Ozone |
| Answer» D. Ozone | |
| 183. |
Which of the following can be inactivated using ozone? |
| A. | Algae |
| B. | Fungi |
| C. | Protozoa |
| D. | All microbes |
| Answer» C. Protozoa | |
| 184. |
Which of these is not an advantage of Ozonation? |
| A. | Reaction with bacteria |
| B. | Organics degradation |
| C. | Equipment costs |
| D. | Chemicals |
| Answer» C. Equipment costs | |
| 185. |
Which of the following is not a disadvantage of Ozonation? |
| A. | Chemicals |
| B. | Costs |
| C. | Energy |
| D. | Fire hazard |
| Answer» A. Chemicals | |
| 186. |
Which of the following is not removed by Ozonation? |
| A. | Iron |
| B. | Manganese |
| C. | Magnesium |
| D. | Bacteria |
| Answer» C. Magnesium | |
| 187. |
What is the maximum time required for ozone degradation? |
| A. | 15 minutes |
| B. | 30 minutes |
| C. | 45 minutes |
| D. | 60 minutes |
| Answer» B. 30 minutes | |
| 188. |
What is the average ozone concentration created during Ozonation? |
| A. | 1000 mg/l |
| B. | 5000 mg/l |
| C. | 10000 mg/l |
| D. | 15000 mg/l |
| Answer» C. 10000 mg/l | |
| 189. |
Which of the following is not correct regarding Ozonation? |
| A. | Does not requires chemicals |
| B. | Eliminates bad taste |
| C. | Eliminates odour |
| D. | Operational costs are low |
| Answer» D. Operational costs are low | |
| 190. |
What is the colour of ozone? |
| A. | Violet |
| B. | White |
| C. | Grey |
| D. | Colourless |
| Answer» D. Colourless | |
| 191. |
Ozone is formed by the interaction of _______ |
| A. | UV or O2 |
| B. | O and O2 |
| C. | O and UV |
| D. | O2 and CO |
| Answer» A. UV or O2 | |
| 192. |
In which year was the structure of ozone determined? |
| A. | 1865 |
| B. | 1875 |
| C. | 1885 |
| D. | 1895 |
| Answer» A. 1865 | |
| 193. |
In which year was the ozone named? |
| A. | 1829 |
| B. | 1839 |
| C. | 1849 |
| D. | 1859 |
| Answer» B. 1839 | |
| 194. |
At what pH ozonation is carried out? |
| A. | 8 |
| B. | 9 |
| C. | 11 |
| D. | 7 |
| Answer» A. 8 | |
| 195. |
Photo catalysis uses which of the following methods to produce free radicals? |
| A. | UV rays |
| B. | UV + TiO2 |
| C. | Ozone + UV |
| D. | TiO2 |
| Answer» B. UV + TiO2 | |
| 196. |
How is the electrical requirement for the ozonation process expressed mathematically? |
| A. | EE/O =EEt/ Vlog(Ci-Cf) |
| B. | EE/O =EEt/ (Ci-Cf) |
| C. | EE/O =EEt Vlog(Ci-Cf) |
| D. | EE/O =EEt(Ci-Cf) |
| Answer» A. EE/O =EEt/ Vlog(Ci-Cf) | |
| 197. |
What are the byproducts of the breakdown of the organic compounds by UV rays? |
| A. | CO |
| B. | CO2 + H2O |
| C. | H2CO3 and water |
| D. | CO + H2O |
| Answer» B. CO2 + H2O | |
| 198. |
In what range is the EE/O present in order to reduce one log of reduction? |
| A. | 0-20 KWH |
| B. | 20-265 KWH |
| C. | 265-365 KWH |
| D. | 365-650 KWH |
| Answer» B. 20-265 KWH | |
| 199. |
Primary sludge includes __________ |
| A. | Total suspended solids |
| B. | Suspended solids |
| C. | Removable solids |
| D. | Settleable solids |
| Answer» D. Settleable solids | |
| 200. |
Which of the following methods are used in rural communities? |
| A. | Aerobic digestion |
| B. | Mechanical dewatering |
| C. | Dewatering |
| D. | Composting |
| Answer» D. Composting | |
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