MCQOPTIONS
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MCQOPTIONS
This section includes 528 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Water effluent generated in printing industry is decolourised by |
| A. | ion exchange technique. |
| B. | reverse osmosis. |
| C. | electrolytic decomposition. |
| D. | adsorption. |
| Answer» D. adsorption. | |
| 252. |
Which of the following causes death by asphyxiation, if its presence in atmospheric air exceeds maximum allowable concentration (i.e. > 50 ppm) ? |
| A. | Benzopyrene |
| B. | Peroxyacyl nitrate |
| C. | Carbon monoxide |
| D. | Sulphur dioxide |
| Answer» D. Sulphur dioxide | |
| 253. |
The function of skimming tank in sewage treatment is to remove __________ substances. |
| A. | dissolved solid |
| B. | suspended solid |
| C. | oil & fatty |
| D. | gritty & inorganic |
| Answer» D. gritty & inorganic | |
| 254. |
Thermal pollution due to excessive heat & temperature in the working place causes |
| A. | reduction in working efficiency of manpower. |
| B. | fatigue. |
| C. | high breathing rate. |
| D. | all (a), (b) & (c). |
| Answer» E. | |
| 255. |
Which of the following is not a natural source of air pollution ? |
| A. | Volcanic eruptions and lightening discharges. |
| B. | Biological decay of vegetable matter. |
| C. | Photochemical oxidation of organic matter. |
| D. | None of these. |
| Answer» E. | |
| 256. |
Fresh domestic sewage is __________ in color. |
| A. | grey |
| B. | dark brown |
| C. | red |
| D. | black |
| Answer» B. dark brown | |
| 257. |
Color test of water is done with an instrument called |
| A. | tintometer |
| B. | colorimeter |
| C. | electro-chemical cell |
| D. | turbidimeter |
| Answer» B. colorimeter | |
| 258. |
Dose of chlorine for disinfection of water is about __________ mg/litre of water. |
| A. | 0.01 |
| B. | 0.1 |
| C. | 0.3 |
| D. | 1 |
| Answer» E. | |
| 259. |
TLV of lead for public sewer/waste water is about __________ ppm. |
| A. | 1 |
| B. | 25 |
| C. | 150 |
| D. | 650 |
| Answer» B. 25 | |
| 260. |
Biological oxidation ponds remove organic matters present in the polluted water by |
| A. | using the activities of bacteria and other micro organisms. |
| B. | aerobic oxidation. |
| C. | both (a) & (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 261. |
Which of the following fine dust removal equipments is the most efficient ? |
| A. | Bag filter |
| B. | Scrubber |
| C. | Electrostatic precipitator |
| D. | Cyclone separator |
| Answer» D. Cyclone separator | |
| 262. |
Smog is not formed due to the presence of __________ in the atmosphere. |
| A. | SO2 |
| B. | NOx |
| C. | CO2 |
| D. | any of these |
| Answer» D. any of these | |
| 263. |
The most commonly used chemical coagulant in water treatment is |
| A. | ferrous sulphate |
| B. | alum |
| C. | lime |
| D. | hydrazine |
| Answer» C. lime | |
| 264. |
World environment day is observed every year on the 5th of |
| A. | June |
| B. | December |
| C. | July |
| D. | September |
| Answer» B. December | |
| 265. |
Noise level during normal conversation among men is about __________ decibles. |
| A. | 10 |
| B. | 45 |
| C. | 90 |
| D. | 115 |
| Answer» C. 90 | |
| 266. |
Water filtration rate in a rapid sand filter ranges from __________ kilolitres/m2/hr. |
| A. | 0.1 to 1 |
| B. | 3 to 6 |
| C. | 10 to 15 |
| D. | 15 to 20 |
| Answer» C. 10 to 15 | |
| 267. |
Radioactive substances present in the polluted water stream can be removed by |
| A. | biological oxygen treatment. |
| B. | coagulation and filtration. |
| C. | adsorption in ion exchange materials. |
| D. | none of these. |
| Answer» D. none of these. | |
| 268. |
Which is the most widely used coagulant for the treatment of turbid water ? |
| A. | Alum (aluminium sulphate) |
| B. | Lime |
| C. | Ferric chloride |
| D. | Sodium aluminate |
| Answer» B. Lime | |
| 269. |
Black smoke coming out of the chimney of a furnace is an indication of the use of __________ in the furnace. |
| A. | low amount of excess combustion air |
| B. | large quantity of excess combustion air |
| C. | hydrocarbon fuel |
| D. | pulverised coal as fuel |
| Answer» B. large quantity of excess combustion air | |
| 270. |
Atmospheric pollution caused by the exhaust gas of supresonic transport air-crafts is mostly in the atmospheric region called |
| A. | thermosphere |
| B. | stratosphere |
| C. | troposphere |
| D. | mesosphere |
| Answer» C. troposphere | |
| 271. |
Presence of __________ in water stream are deleterious to aquatic life. |
| A. | soluble and toxic organics. |
| B. | suspended solids. |
| C. | heavy metals and cynides. |
| D. | all (a), (b) & (c). |
| Answer» E. | |
| 272. |
Carcinogenic air pollutants cause |
| A. | bone decay |
| B. | cancer |
| C. | asphyxiation (suffocation) |
| D. | anemia |
| Answer» C. asphyxiation (suffocation) | |
| 273. |
Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is __________ decibels. |
| A. | 35 |
| B. | 75 |
| C. | 95 |
| D. | 105 |
| Answer» C. 95 | |
| 274. |
The maximum CO2 is emitted into the atmosphere by |
| A. | combustion |
| B. | urea |
| C. | biomass burning |
| D. | trees |
| Answer» B. urea | |
| 275. |
Which of the following is an adsorbant used for the removal of SO2 from gas/air ? |
| A. | Bog iron |
| B. | Limestone powder or alkalised alumina |
| C. | Silica gel |
| D. | Active carbon |
| Answer» C. Silica gel | |
| 276. |
In large thermal power stations very fine particulates present in flue gas are removed by |
| A. | wet scrubber |
| B. | bag filter |
| C. | electrostatic precipitators |
| D. | dust catcher |
| Answer» D. dust catcher | |
| 277. |
A standard test for determination of hardness in water is termed as __________ test. |
| A. | EDTA |
| B. | electometric |
| C. | total count |
| D. | presumptive |
| Answer» B. electometric | |
| 278. |
Reinglemann chart is used for the measurement of the |
| A. | combustibles present in automobile exhaust. |
| B. | smoke density from a chimey. |
| C. | exhaust gas density. |
| D. | flue gas temperature. |
| Answer» C. exhaust gas density. | |
| 279. |
Pollution by particulate matter emission in the atmosphere does not take place during metal |
| A. | grinding |
| B. | machining |
| C. | cutting |
| D. | polishing |
| Answer» E. | |
| 280. |
Which is the most practical and economical method for removal of suspended solid matter from polluted water ? |
| A. | Sedimentation |
| B. | Skimming off |
| C. | Chlorination |
| D. | Biological oxidation |
| Answer» B. Skimming off | |
| 281. |
Threshold limit value (TLV) of CO in air is __________ ppm. |
| A. | 5 |
| B. | 50 |
| C. | 2000 |
| D. | 5000 |
| Answer» C. 2000 | |
| 282. |
Which of the following is the most active zone of atmosphere in which weathering events like rain, storm & lightning occur ? |
| A. | Thermosphere |
| B. | Troposphere |
| C. | Stratosphere |
| D. | none of these |
| Answer» C. Stratosphere | |
| 283. |
Presence of soluble organics in polluted water causes |
| A. | undesirable plants growth. |
| B. | depletion of oxygen. |
| C. | fire hazards. |
| D. | explosion hazards. |
| Answer» C. fire hazards. | |
| 284. |
In troposphere (the weather domain), the temperature 't' at height 'h' above the spa level in metres is given by (where, temperature at sea level is 15°C and t is in °C.)$ |
| A. | t = 15 - 0.0065h |
| B. | t = 15 + 0.0065h |
| C. | t = 0.0035h -15 |
| D. | t = 15 - 0.0035h |
| Answer» B. t = 15 + 0.0065h | |
| 285. |
__________ plant emits large amount of SO2 as an air pollutant. |
| A. | Nitric acid |
| B. | Sulphuric acid |
| C. | Chloralkali |
| D. | Iron & steel |
| Answer» C. Chloralkali | |
| 286. |
Which of the following is a secondary air pollutant ? |
| A. | Photochemical smog |
| B. | Sulphur dioxide |
| C. | Nitrogen dioxide |
| D. | Dust particles |
| Answer» B. Sulphur dioxide | |
| 287. |
Presence of nitrates in water in excess of 50 ppm causes |
| A. | mathenoglobenemia |
| B. | gastroentetitis |
| C. | asphyxiation |
| D. | tooth decay |
| Answer» B. gastroentetitis | |
| 288. |
Ambient noise level can be reduced by __________ decibels by planting trees (like coconut, neem etc.) near public utility buildings (like hospitals & schools). |
| A. | 43497 |
| B. | 43743 |
| C. | 15-20 |
| D. | 25-30 |
| Answer» C. 15-20 | |
| 289. |
5-200 μm size particles are called$ |
| A. | colloids or aerosols |
| B. | powder |
| C. | dust |
| D. | smoke |
| Answer» B. powder | |
| 290. |
The detrimental effect on organism and water quality with temperature rise of aquatic system is the reduction of __________ of water. |
| A. | dissolved oxygen content |
| B. | biological oxygen demand |
| C. | vapor pressure |
| D. | all (a), (b) and (c) |
| Answer» B. biological oxygen demand | |
| 291. |
The Killer gas which caused Bhopal gas tragedy in 1984 was |
| A. | phosgene |
| B. | methyl iso-cynate (MIC) |
| C. | carbon monoxide |
| D. | sulphur dioxide |
| Answer» C. carbon monoxide | |
| 292. |
Lead exhausted in the atmosphere by automobiles using leaded petrol (i.e. tetraethyl lead for improving octane number) is a lethal air pollutant which causes |
| A. | paralysis of muscles & loss of appetite. |
| B. | nervous depression. |
| C. | gastritis & diarrhea. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 293. |
Permissible safe limit (TLV) of __________ toxic gas is 100-1000 parts per million (ppm). |
| A. | highly |
| B. | moderately |
| C. | extremely |
| D. | very extremely |
| Answer» C. extremely | |
| 294. |
Noise level inside a jet air liner in normal flight is about __________ decibels. |
| A. | 80 |
| B. | 100 |
| C. | 125 |
| D. | 145 |
| Answer» C. 125 | |
| 295. |
The principal gas evolved from sludge digestion tank is |
| A. | CO |
| B. | CO2 |
| C. | CH4 |
| D. | N2 |
| Answer» D. N2 | |
| 296. |
Carbon monoxide is a pollutant, which causes |
| A. | respiratory disease (e.g. asthma). |
| B. | asphyxiation (suffocation) leading to death. |
| C. | retardation in crop growth. |
| D. | damage to building materials like marble. |
| Answer» C. retardation in crop growth. | |
| 297. |
In sewage treatment, the detention period allowed for oxidation ponds ranges from __________ weeks. |
| A. | 1 to 2 |
| B. | 4 to 5 |
| C. | 9 to 10 |
| D. | 15 to 20 |
| Answer» C. 9 to 10 | |
| 298. |
High noise levels produced during operation of fans and compressors can be reduced by using |
| A. | mufflers (silencers). |
| B. | accoustical absorbent. |
| C. | lagging of noisy duct. |
| D. | none of these. |
| Answer» B. accoustical absorbent. | |
| 299. |
The upper layer of atmosphere is called the |
| A. | stratosphere |
| B. | troposphere |
| C. | ionosphere |
| D. | none of these |
| Answer» B. troposphere | |
| 300. |
Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxant is ‚â• __________ percent.$ |
| A. | 84 |
| B. | 88 |
| C. | 80 |
| D. | 92 |
| Answer» B. 88 | |