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.
| 301. |
Maximum permissible residual chlorine in treated water should be __________ mg/litre. |
| A. | 0.001 to 0.01 |
| B. | 02 to 0.3 |
| C. | 2 to 3 |
| D. | 5 to 10 |
| Answer» C. 2 to 3 | |
| 302. |
Presence of bacteria in potable (drinking) water causes |
| A. | turbidity |
| B. | disease |
| C. | bad odour |
| D. | bad taste & colour |
| Answer» C. bad odour | |
| 303. |
Salt content in sea water is about __________ percent. |
| A. | 0.5 |
| B. | 1 |
| C. | 3.5 |
| D. | 10 |
| Answer» D. 10 | |
| 304. |
There are five concentric layers within the atmosphere which is differentiated on the basis of temperature. The atmospheric layer which lies close to the earth's surface in which human being along with other organisms live is called troposphere. The rate at which air temperature in the troposphere gradually decreases with height is about __________ °C/km.$ |
| A. | 0.05 |
| B. | 1 |
| C. | 6.5 |
| D. | 15 |
| Answer» D. 15 | |
| 305. |
Maximum permissible limit of mercury in human blood is __________ micrograms/100 c.c. |
| A. | 1 |
| B. | 7 |
| C. | 19 |
| D. | 82 |
| Answer» C. 19 | |
| 306. |
Peroxyacyl nitrate (PAN), a pollutant is found in the |
| A. | automobile exhaust. |
| B. | flue gas of coal based power plant. |
| C. | exhaust of nitric acid plant. |
| D. | exhaust of sulphuric acid plant. |
| Answer» B. flue gas of coal based power plant. | |
| 307. |
High concentration of carcinogenic hydrocarbon pollutants in atmospheric air causes |
| A. | cancer |
| B. | silicosis |
| C. | respiratory disease (e.g., asthma) |
| D. | reduced crop yield |
| Answer» B. silicosis | |
| 308. |
Maximum permissible concentration (i.e. TLV) of DDT in public water supply system is __________ micro gram (μ g)/litre.$ |
| A. | 2 |
| B. | 42 |
| C. | 332 |
| D. | 1050 |
| Answer» C. 332 | |
| 309. |
Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air exceeds __________ percent (by volume). |
| A. | 1 |
| B. | 3 |
| C. | 7 |
| D. | 20 |
| Answer» E. | |
| 310. |
A 'body' which allows the short wavelength incoming solar radiation to enter in, but does not allow long wave length outgoing infra red radiation to escape out is called the |
| A. | global warming |
| B. | green house |
| C. | atmospheric effect |
| D. | ionosphere |
| Answer» C. atmospheric effect | |
| 311. |
CFC (chloro fluoro carbon) is very highly reactive in causing depletion of ozone layer in the atmosphere. Each atom of chlorine liberated from CFC is capable of decomposing __________ molecules of ozones. |
| A. | 102 |
| B. | 105 |
| C. | 109 |
| D. | 1015 |
| Answer» C. 109 | |
| 312. |
The biological decomposition of organic substances in wastes controlled conditions is called |
| A. | incineration |
| B. | biological oxidation |
| C. | composting |
| D. | none of these |
| Answer» D. none of these | |
| 313. |
Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan |
| A. | with greater number of blades. |
| B. | of increased diameter. |
| C. | both (a) & (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 314. |
Lagooning process is mainly a means of the |
| A. | sludge disposal. |
| B. | reduction of excessive flow in sewers. |
| C. | biological treatment of wastes. |
| D. | none of these. |
| Answer» B. reduction of excessive flow in sewers. | |
| 315. |
Noise pollution level in a chemical plant is expressed in |
| A. | roentgen |
| B. | decibel |
| C. | hertz |
| D. | none of these |
| Answer» C. hertz | |
| 316. |
The resistance of water to the passage of light through it is a measure of the |
| A. | turbidity |
| B. | color |
| C. | hardness |
| D. | dissolved gases |
| Answer» B. color | |
| 317. |
Presence of dissolved impurities of __________ is responsible for the red brownish color of water. |
| A. | carbonates |
| B. | bi-carbonates |
| C. | iron & manganese |
| D. | arsenic |
| Answer» D. arsenic | |
| 318. |
Lagoons used for purification of polluted water |
| A. | are large shallow artificial lakes also known as clarification lakes, maturation ponds or oxidation ponds. |
| B. | use micro-organisms/bacteria in presence of dissolved oxygen. |
| C. | gives an excellent final effluent (with 3 to 4 lagoons arranged in series) having suspended solid < 1 mg/litre and BOD = 3.8 mg/litre. |
| D. | all (a), (b) & (c). |
| Answer» E. | |
| 319. |
Which of the following is the most severe air pollutant ? |
| A. | hydrocarbons |
| B. | NOx |
| C. | SO2 |
| D. | CO |
| Answer» C. SO2 | |
| 320. |
Deaeration of high pressure boiler feed water is done to reduce |
| A. | foaming from boilers. |
| B. | its dissolved oxygen content. |
| C. | its silica content. |
| D. | caustic embrittlement. |
| Answer» C. its silica content. | |
| 321. |
Dissolved oxygen content in river water is around __________ ppm. |
| A. | 5 |
| B. | 100 |
| C. | 250 |
| D. | 500 |
| Answer» B. 100 | |
| 322. |
Maximum allowable noise exposure limits for a man working for 8 hours a day in a noisy chemical plant is about __________ decibels. |
| A. | 20 |
| B. | 60 |
| C. | 90 |
| D. | 120 |
| Answer» D. 120 | |
| 323. |
Green house gases blanket/block the infrared radiation from earth's surface to the atmosphere leading to its progressive warming up. Which of the following gases does not exhibit green house effect ? |
| A. | CO2 |
| B. | H2 |
| C. | SO3 |
| D. | N2 |
| Answer» D. N2 | |
| 324. |
Which of the following is an adsorbant for removal of nitrogen oxides from gas/air ? |
| A. | Active carbon |
| B. | Silica gel |
| C. | Bog iron (iron oxide) |
| D. | Pulverised limestone |
| Answer» C. Bog iron (iron oxide) | |
| 325. |
Corrosion in boilers can be prevented by |
| A. | deaeration of feed water. |
| B. | enhancing pH of feed water by adding alkali. |
| C. | feeding sodium sulphite or hydrazine phosphate to the boilers, which combines with oxygen and prevents corrosion. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 326. |
The pH value of potable water should be between |
| A. | 1 to 1.5 |
| B. | 6.5 to 8 |
| C. | 13 to 14 |
| D. | 4 to 5 |
| Answer» C. 13 to 14 | |
| 327. |
Iron & manganese present in the polluted water is removed by |
| A. | simple filtration. |
| B. | oxidation followed by settling & filtration. |
| C. | chemical coagulation. |
| D. | chlorination only. |
| Answer» C. chemical coagulation. | |
| 328. |
Arsenic pollutant is not generated in____industries. |
| A. | tanneries |
| B. | glass & ceramic |
| C. | beverages |
| D. | any of these. |
| Answer» D. any of these. | |
| 329. |
__________ can not control the noise pollution. |
| A. | Use of silencers |
| B. | Green house gases |
| C. | Vibration damping |
| D. | Tree plantation |
| Answer» C. Vibration damping | |
| 330. |
Which of the following is the most lethal water pollutant ? |
| A. | Phenol and cynide |
| B. | Chlorine |
| C. | Alkalis |
| D. | Suspended solids |
| Answer» B. Chlorine | |
| 331. |
Main pollutants released from petroleum refineries is |
| A. | CO, SO2 & H2S. |
| B. | CO2, NO & SO3. |
| C. | CO2, H2S & NO2. |
| D. | SO3, NO2 & CO2. |
| Answer» B. CO2, NO & SO3. | |
| 332. |
The permissible color for domestic water supply is __________ ppm. |
| A. | 1 |
| B. | 20 |
| C. | 100 |
| D. | 1000 |
| Answer» C. 100 | |
| 333. |
Lung cancer & DNA breakage are the major ill effects of excessive ozone exposure to human beings. Ozone layer depletion in the atmosphere is mainly caused by the presence of |
| A. | CO2 |
| B. | SO2 |
| C. | hydrocarbons |
| D. | CFC (chloro fluoro carbon) |
| Answer» E. | |
| 334. |
Carbonaceous particles having size less than 1 μm are called$ |
| A. | grit |
| B. | aggregates |
| C. | aerosols |
| D. | smoke |
| Answer» E. | |
| 335. |
Inorganic impurities causing water pollution is |
| A. | fats |
| B. | carbohydrates |
| C. | salts of metals |
| D. | protein |
| Answer» D. protein | |
| 336. |
Out of the following, TLV of __________ is the minimum (about 0.02 ppm). |
| A. | phosgene |
| B. | bromine |
| C. | MIC (methyl iso-cynate) |
| D. | ozone |
| Answer» D. ozone | |
| 337. |
Which of the following air pollutants is not toxic to vegetation i.e., doesn't cause vegetation damage ? |
| A. | Smog & ozone |
| B. | Hydrogen fluoride & nitrogen oxides |
| C. | Sulphur dioxide & spray of weed killers |
| D. | Carbon monoxide |
| Answer» E. | |
| 338. |
Noise level heard inside a bus in busy city traffic or inside a sub-way train corresponds to about __________ decibels. |
| A. | 75 |
| B. | 95 |
| C. | 120 |
| D. | 140 |
| Answer» C. 120 | |
| 339. |
COD of raw municipal sewage may be in the range of about __________ mg/litre. |
| A. | 43497 |
| B. | 43743 |
| C. | 90-120 |
| D. | 1500-2500 |
| Answer» D. 1500-2500 | |
| 340. |
The major reason of hydrodynamic noise (i.e., noise resulting from liquid flow) is |
| A. | pipe vibrations. |
| B. | cavitation. |
| C. | boundary layer separation. |
| D. | fluctuation in liquid flow. |
| Answer» C. boundary layer separation. | |
| 341. |
The density of the gases (present in air) decreases with increasing altitude to such an extent, that about 70% of the mass of atmospheric air is found in the lower 5 km. of the atmosphere. This lower region of atmosphere is called the |
| A. | ionosphere |
| B. | troposphere |
| C. | stratosphere |
| D. | none of these |
| Answer» C. stratosphere | |
| 342. |
Which of the following is not a weightless pollutant ? |
| A. | SPM |
| B. | Thermal pollution |
| C. | Radioactive rays |
| D. | Noise pollution |
| Answer» B. Thermal pollution | |
| 343. |
__________ is removed from water by lime-soda process. |
| A. | Foul smell and taste |
| B. | Iron and manganese |
| C. | Temporary hardness |
| D. | Permanent hardness |
| Answer» D. Permanent hardness | |
| 344. |
The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated. |
| A. | decreases. |
| B. | increases. |
| C. | remains constant. |
| D. | may increase or decrease ; depends on the chemical characteristics of polluted water. |
| Answer» B. increases. | |
| 345. |
Which of the following gases is having the widest explosion limit (about 2 to 81% gas in gas-air mixture), rendering it the property of the most explosive gas ? |
| A. | Hydrogen |
| B. | Acetylene |
| C. | Carbon monoxide |
| D. | Ammonia |
| Answer» C. Carbon monoxide | |
| 346. |
There are thirteen metals which are treated as pollutants. Which of the following metals is not a pollutant ? |
| A. | Mercury |
| B. | Arsenic |
| C. | Aluminium |
| D. | Lead |
| Answer» D. Lead | |
| 347. |
When the concentration of SO2 in air is greater than __________ ppm, it gives a pungent smell. |
| A. | 0.01 |
| B. | 0.1 |
| C. | 1 |
| D. | 4 |
| Answer» E. | |
| 348. |
Solid content in most of the domestic sewage is about __________ percent. |
| A. | 0.001 |
| B. | 0.1 |
| C. | 5 |
| D. | 10 |
| Answer» C. 5 | |
| 349. |
The main type of sludge gas evolved during sewage treatment in Imhoff tank is |
| A. | CO2 |
| B. | CH4 |
| C. | CO |
| D. | H2 |
| Answer» C. CO | |
| 350. |
Which of the following sources is responsible for maximum air pollution ? |
| A. | Industrial chimney exhaust. |
| B. | Forest fire. |
| C. | Automobiles exhaust. |
| D. | Photochemical oxidation of organic matter. |
| Answer» D. Photochemical oxidation of organic matter. | |