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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.
501. |
Infective bacteria in water is killed by the __________ process. |
A. | sterilisation |
B. | aeration |
C. | disinfection |
D. | none of these |
Answer» B. aeration | |
502. |
Which is the best and the most effective method for the removal of organic contaminant present in the polluted water in very small quantity (say < 200 mg/litre)? |
A. | Lagooning |
B. | Activated carbon adsorption |
C. | Biological oxidation pond |
D. | Chemical coagulation |
Answer» C. Biological oxidation pond | |
503. |
Which of the following pollutants is absent in the emissions from a fertiliser plant ? |
A. | SO2 & SO3 |
B. | NO2 |
C. | NH3 |
D. | CO |
Answer» E. | |
504. |
The type of bacteria which is active in trickling filter during biological treatment of sewage is the __________ bacteria. |
A. | anaerobic |
B. | saphrophytic |
C. | aerobic |
D. | parasitic |
Answer» D. parasitic | |
505. |
The concentration of water vapour in troposphere, which depends upon the altitude & temperature varies in the range of zero to __________ percent. |
A. | 1 |
B. | 4 |
C. | 8 |
D. | 12 |
Answer» C. 8 | |
506. |
Sound produced by an automobile horn heard at a distance of 1.5 metres corresponds to about __________ decibels. |
A. | 90 |
B. | 120 |
C. | 150 |
D. | 180 |
Answer» C. 150 | |
507. |
Exposure to chemicals having carcinogenic properties cause |
A. | dermatitis (skin disorder) |
B. | cancer |
C. | asphyxiation (suffocation) |
D. | asthma |
Answer» C. asphyxiation (suffocation) | |
508. |
H2S present in gaseous stream can be removed by adsorption on |
A. | silica gel |
B. | active carbon |
C. | bog iron |
D. | limestone powder |
Answer» D. limestone powder | |
509. |
Smog is |
A. | nothing but black smoke. |
B. | a combination of smoke and fog. |
C. | a liquid particle resulting from vapor condensation. |
D. | a solid particle e.g. flyash. |
Answer» C. a liquid particle resulting from vapor condensation. | |
510. |
Most of the atmospheric air pollutants are present in large quantity in |
A. | stratosphere |
B. | thermosphere |
C. | trophosphere |
D. | mesosphere |
Answer» D. mesosphere | |
511. |
Persons working in cement plants and limestone quarries are more prone to disease like |
A. | cancer |
B. | asthma |
C. | silicosis |
D. | flourosis (bone disease) |
Answer» D. flourosis (bone disease) | |
512. |
During which of the following operating conditions of an automobile, carbon monoxide content in the exhaust gas is maximum ? |
A. | Idle running |
B. | Acceleration |
C. | Cruising |
D. | Deaccelaration |
Answer» B. Acceleration | |
513. |
Most efficient and suitable dust removal equipment for removal of flyash from flue gas in a thermal power plant is the |
A. | gravity settling chamber |
B. | cyclone separator |
C. | electrostatic precipitator |
D. | bag filter |
Answer» D. bag filter | |
514. |
The main pollutant in waste water discharged from a petroleum refinery is oil (both in free and emulsified form). Free oil is removed by |
A. | biological oxygen pond. |
B. | aerated lagoons. |
C. | trickling filters. |
D. | gravity separator having oil skimming devices. |
Answer» E. | |
515. |
In water treatment plant, zeolite process is used to remove the __________ of water. |
A. | acidity |
B. | alkalinity |
C. | hardness |
D. | iron & zinc |
Answer» D. iron & zinc | |
516. |
Particulates (< 1μm size) remaining suspended in air indefinitely and transported by wind currents are called |
A. | fumes |
B. | mists |
C. | smoke |
D. | aerosols |
Answer» E. | |
517. |
Maximum allowable concentration of CO2 in air for safe working is __________ ppm (parts per million). |
A. | 50 |
B. | 1000 |
C. | 2000 |
D. | 5000 |
Answer» E. | |
518. |
The term Biological Oxygen Demand (BOD) is used in relation to |
A. | potable water |
B. | cooling water |
C. | distilled water |
D. | industrial effluents |
Answer» E. | |
519. |
Which of the following is the most detrimental for water used in high pressure boiler ? |
A. | Silica |
B. | Turbidity |
C. | Phenol |
D. | Dissolved oxygen |
Answer» B. Turbidity | |
520. |
Exposure to small amount of __________ results in high blood pressure & heart disease in human beings. |
A. | hydrogen sulphide |
B. | mercury |
C. | cadmium |
D. | asbestos |
Answer» D. asbestos | |
521. |
Operating principle of cyclone separator is based on the action of __________ dust particles. |
A. | diffusion of |
B. | centrifugal force on |
C. | gravitational force on |
D. | electrostatic force on |
Answer» C. gravitational force on | |
522. |
Presence of non-biodegradable substances, like alkyl benzene sulphonate (ABS) from the detergents in polluted water stream causes |
A. | fire hazards. |
B. | explosion hazards. |
C. | persistent foam. |
D. | depletion of dissolved oxygen. |
Answer» D. depletion of dissolved oxygen. | |
523. |
Scale formation in boiler is controlled by |
A. | preheating of feed water. |
B. | reduction in hardness, silica & alumina in feed water. |
C. | keeping the pH value of feed water just below 7. |
D. | eliminating H2S in feed water. |
Answer» C. keeping the pH value of feed water just below 7. | |
524. |
The commonest form of iron & manganese found in ground water as pollutant is in the form of their |
A. | carbonates |
B. | bi-carbonates |
C. | chlorides |
D. | sulphides |
Answer» C. chlorides | |
525. |
Pick out the wrong statement pertaining to 'green house' for the plants. |
A. | 'Green house' (made of glass) allows visible sunlight (i.e., short wavelength solar radiation like ultra-violet rays) to pass through the glass and heat up the soil thereby warming up plants inside it. |
B. | The emitted longer wavelength radiation (e.g., infrared) is partly reflected and partly absorbed by the glass of the green house. |
C. | 'Green house effect' in earth's atmosphere is due to increasing CO2 level in atmosphere. where CO2 acts like the glass of 'green house' thereby warming up the earth's surface. |
D. | 'Green house' is colder than the outside atmosphere. |
Answer» E. | |
526. |
Smoke is produced due to |
A. | insufficient supply of combustion air and insufficient time for combustion. |
B. | poor quality of fuel and improper mixing of fuel & combustion air. |
C. | poor design & overloading of furnace. |
D. | all (a), (b) and (c). |
Answer» E. | |
527. |
Ionisation potential employed in the industrial electrostatic precipitator is of the order of |
A. | 30 to 70 kV DC |
B. | 30 to 70 kV AC |
C. | 230 V AC |
D. | 230 V DC |
Answer» B. 30 to 70 kV AC | |
528. |
Suspended solid present in the waste water generated in blast furnace gas cooling and cleaning plant is removed by |
A. | biological oxygen pond. |
B. | radial settling tank (thickener) using coagulant (lime & ferrous sulphate). |
C. | lagoons. |
D. | filtration. |
Answer» C. lagoons. | |