MCQOPTIONS
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MCQOPTIONS
This section includes 8247 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 4551. |
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 | |
| 4552. |
Brown spots in fabrics will be caused by washing with water containing large amount of . |
| A. | iron |
| B. | zinc |
| C. | iodine |
| D. | bromine |
| Answer» B. zinc | |
| 4553. |
Maximum permissible concentration (i.e. TLV) of DDT in public water supply system is __________ micro gram ( g)/litre. |
| A. | 2 |
| B. | 42 |
| C. | 332 |
| D. | 1050 |
| Answer» C. 332 | |
| 4554. |
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 | |
| 4555. |
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 | |
| 4556. |
Fresh domestic sewage is __________ in color. |
| A. | grey |
| B. | dark brown |
| C. | red |
| D. | black |
| Answer» B. dark brown | |
| 4557. |
White smoke coming out of the chimney of a furnace indicates the use of |
| A. | low excess air. |
| B. | very high excess air. |
| C. | gaseous fuel in the furnace. |
| D. | liquid fuel in the furnace. |
| Answer» C. gaseous fuel in the furnace. | |
| 4558. |
TLV of NO2 & NO exposure for the human being is 5 & 25 ppm respectively. Prolonged exposure of human being to NO2 causes |
| A. | skin disorder |
| B. | bronchitis |
| C. | bone disease |
| D. | cancer |
| Answer» C. bone disease | |
| 4559. |
Sulphur dioxide present in the industrial chimney exhaust gases causes |
| A. | respiratory & lung disease. |
| B. | reduction in plant's productivity owing to acid rain. |
| C. | corrosion of building materials. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 4560. |
A man exposed to excessive noise level in the working environment may suffer from |
| A. | hearing loss |
| B. | rupture of ear drum |
| C. | nervousness & fatigue |
| D. | all (a), (b) & (c) |
| Answer» E. | |
| 4561. |
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 | |
| 4562. |
Salt content in sea water is about __________ percent. |
| A. | 0.5 |
| B. | 1 |
| C. | 3.5 |
| D. | 10 |
| Answer» D. 10 | |
| 4563. |
Noise level inside a jet air liner in normal flight is about __________ decibels. |
| A. | 80 |
| B. | 100 |
| C. | 125 |
| D. | 145 |
| Answer» C. 125 | |
| 4564. |
What is the major constituents of waste/polluted water discharged from textile, pulp & paper, tanning, distillary, dairy and meat packing industries ? |
| A. | Radioactive substances |
| B. | Natural organic products |
| C. | Inorganic pollutants |
| D. | None of these |
| Answer» C. Inorganic pollutants | |
| 4565. |
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 | |
| 4566. |
Presence of nitrogen and phosphorous in waste water discharged into lakes and ponds causes |
| A. | foaming |
| B. | odour nuisances |
| C. | undesirable plant growth |
| D. | turbidity |
| Answer» D. turbidity | |
| 4567. |
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 | |
| 4568. |
Maximum permissible limit of mercury in human blood is __________ micrograms/100 c.c. |
| A. | 1 |
| B. | 7 |
| C. | 19 |
| D. | 82 |
| Answer» C. 19 | |
| 4569. |
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. | |
| 4570. |
Oilish impurities present the effluent discharged from the electroplating industry is normally not removed by |
| A. | chemical coagulation |
| B. | floatation & skimming |
| C. | centrifugation |
| D. | ultrafiltration |
| Answer» B. floatation & skimming | |
| 4571. |
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 | |
| 4572. |
Water filtration rate in a slow sand filter ranges from __________ litres/m2/hr. |
| A. | 10 to 20 |
| B. | 100 to 200 |
| C. | 1500 to 2500 |
| D. | 4000 to 5000 |
| Answer» C. 1500 to 2500 | |
| 4573. |
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. | |
| 4574. |
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 | |
| 4575. |
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 | |
| 4576. |
Higher concentration of CO2 in atmosphere |
| A. | allows visible solar radiation (ultraviolet) of short wave-length to pass through. |
| B. | reflects and absorbs the longer wavelength (infra-red) radiations. |
| C. | prevents solar heat being radiated out completely, resulting in 'heat trap' i.e., global warming. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 4577. |
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 | |
| 4578. |
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. | |
| 4579. |
In the context of the chemical process industries, the term BOD is normally associated with the |
| A. | characterisation of solid wastes. |
| B. | organic concentration in gaseous effluents. |
| C. | characterisation of liquid effluents. |
| D. | characterisation of boiler feed water. |
| Answer» D. characterisation of boiler feed water. | |
| 4580. |
Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels. |
| A. | 85 |
| B. | 105 |
| C. | 125 |
| D. | 145 |
| Answer» C. 125 | |
| 4581. |
Inhalation of silica dust causes a disease called |
| A. | bronchitis |
| B. | silicosis |
| C. | pneumoconiosis |
| D. | none of these |
| Answer» C. pneumoconiosis | |
| 4582. |
Solid content in most of the domestic sewage is about __________ percent. |
| A. | 0.001 |
| B. | 0.1 |
| C. | 5 |
| D. | 10 |
| Answer» C. 5 | |
| 4583. |
Shouting by a man at his full voice corresponds to a voice level of about __________ decibels. |
| A. | 25 |
| B. | 50 |
| C. | 80 |
| D. | 120 |
| Answer» D. 120 | |
| 4584. |
Carbonaceous particles having size less than 1 m are called |
| A. | grit |
| B. | aggregates |
| C. | aerosols |
| D. | smoke |
| Answer» E. | |
| 4585. |
__________ substances present in sewage are removed in grit chamber during sewage treatment. |
| A. | Organic |
| B. | Fatty |
| C. | Inorganic |
| D. | Dissolved |
| Answer» D. Dissolved | |
| 4586. |
The destruction of water-borne pathogens is termed as disinfection of water. Which of the following is a water disinfectant ? |
| A. | Chlorine |
| B. | Alkalis |
| C. | Benzene hexachloride |
| D. | Alkyl benzene sulphonate (ABS) |
| Answer» B. Alkalis | |
| 4587. |
Disinfection of water is done to destroy pathogenic bacteria and thus prevent water-borne diseases. Disinfection of water may be done by the use of |
| A. | ozone and iodine. |
| B. | chlorine or its compounds. |
| C. | ultraviolet light for irradiation of water. |
| D. | all (a), (b) & (c). |
| Answer» E. | |
| 4588. |
Which of the following processes is involved in the biochemical treatment of sewage effluents ? |
| A. | Oxidation |
| B. | Reduction |
| C. | Dehydration |
| D. | Fermentation |
| Answer» B. Reduction | |
| 4589. |
Infective bacteria in water is killed by the __________ process. |
| A. | sterilisation |
| B. | aeration |
| C. | disinfection |
| D. | none of these |
| Answer» B. aeration | |
| 4590. |
In water treatment, alum[Al2(SO4)3] is used for the process of |
| A. | filtration |
| B. | coagulation |
| C. | sedimentation |
| D. | disinfection |
| Answer» C. sedimentation | |
| 4591. |
Pick out the one which is not a chemical coagulant. |
| A. | Aluminium sulphate |
| B. | Ferrous sulphate |
| C. | Hydrated lime |
| D. | Chloramine |
| Answer» E. | |
| 4592. |
Presence of iron and manganese in water causes |
| A. | reduction in its dissolved oxygen content. |
| B. | discoloration of bathroom fixtures. |
| C. | temporary hardness. |
| D. | none of these. |
| Answer» C. temporary hardness. | |
| 4593. |
Septic tanks are used for the __________ of the deposited solids. |
| A. | separation |
| B. | anaerobic decomposition |
| C. | aerobic decomposition |
| D. | none of these |
| Answer» C. aerobic decomposition | |
| 4594. |
A catalyst promoter |
| A. | improves the activity of a catalyst. |
| B. | acts as a catalyst support. |
| C. | itself has very high activity. |
| D. | all (a), (b) and (c). |
| Answer» B. acts as a catalyst support. | |
| 4595. |
In case of a P.F.R., there |
| A. | may be lateral mixing of fluid. |
| B. | should not be any mixing along the flow path. |
| C. | both (a) and (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 4596. |
For the non-catalytic reaction of particles with surrounding fluid, the time needed to achieve the same fractional conversion for particles of different but unchanging sizes is proportional to the square of particle diameter, when the __________ is the controlling resistance. |
| A. | film diffusion |
| B. | diffusion through ash layer |
| C. | chemical reaction |
| D. | either (a), (b) or (c) |
| Answer» C. chemical reaction | |
| 4597. |
If G (free energy change) for a chemical reaction is very large and negative, then the reaction is |
| A. | not feasible. |
| B. | just feasible. |
| C. | very much feasible. |
| D. | unpredictable as G is no measure of feasibility of a reaction. |
| Answer» D. unpredictable as G is no measure of feasibility of a reaction. | |
| 4598. |
In a zero order reaction, reactants concentration does not change with time and the |
| A. | time for half change is half the time taken for completion of the reaction. |
| B. | time for half change is independent of the initial concentration. |
| C. | time for completion of the reaction is independent of the initial concentration. |
| D. | reaction rate is trebled when the initial concentration is trebled. |
| Answer» B. time for half change is independent of the initial concentration. | |
| 4599. |
Which of the following fixes the volume of a batch reactor for a particular conversion and production rate ? |
| A. | Operating conditions (e.g. pressure and temperature) |
| B. | Rate constant |
| C. | Density of mixture |
| D. | None of these |
| Answer» D. None of these | |
| 4600. |
Volume change for unimolecular type first order reaction , increases __________ with time. |
| A. | linearly |
| B. | exponentially |
| C. | parabolically |
| D. | logarithmically |
| Answer» C. parabolically | |