Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

Radioactive solid nuclear wastes are disposed off by

A. High temperature incineration
B. Pathological incineration
C. Pyrolysis
D. Underground burial in concrete containers
Answer» E.
2.

Most of the atmospheric air pollutants are present in large quantity in

A. Stratosphere
B. Thermosphere
C. Trophosphere
D. Mesosphere
Answer» D. Mesosphere
3.

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
4.

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
5.

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
6.

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
7.

Irradiation of water by ultraviolet light of suitable wavelength is commonly used for disinfection of water in

A. Food industry
B. Municipal sewage treatment
C. Petroleum refinery
D. Iron & steel plant
Answer» B. Municipal sewage treatment
8.

Solid content in most of the domestic sewage is about __________ percent.

A. 0.001
B. 0.1
C. 5
D. 10
Answer» C. 5
9.

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
10.

Which of the following is not a source of ozone emission in the atmosphere?

A. Refrigerators
B. Xerox machines
C. Dermatological photo-therapy equipments
D. High voltage electrical equipments
Answer» B. Xerox machines
11.

Inhalation of silica dust by human being during hand drilling in mica mining, lead & zinc mining, silica refractory manufacture and in foundaries causes

A. Asphyxiation (suffocation)
B. Shortness of breath
C. Tuberculosis
D. All of the above
Answer» E.
12.

World's worst radioactive pollution was caused by nuclear reactor disaster which occured in

A. Arizona (U.S.A.)
B. Chernobyl (undivided U.S.S.R.)
C. Pensylvania (U.S.A.)
D. Moscow (U.S.S.R.)
Answer» C. Pensylvania (U.S.A.)
13.

Particles having diameter greater than 75 μm (micrometer = 10-6 mm) are called

A. Grit
B. Dust
C. Powder
D. Smoke
Answer» B. Dust
14.

TLV of ozone (O₃) and phosgene (COCl₂) in air is __________ ppm.

A. 0.1
B. 25
C. 100
D. 1000
Answer» B. 25
15.

Carcinogenic air pollutants cause

A. Bone decay
B. Cancer
C. Asphyxiation (suffocation)
D. Anemia
Answer» C. Asphyxiation (suffocation)
16.

Noise pollution level in a chemical plant is expressed in

A. Roentgen
B. Decibel
C. Hertz
D. None of these
Answer» C. Hertz
17.

From pollution control point of view, the maximum permissible concentration of sulphur dioxide in atmospheric air is about __________ ppm.

A. 1
B. 5
C. 50
D. 500
Answer» C. 50
18.

A shallow pond in which the sewage is retained and biologically treated is called

A. Oxidation
B. Imhoff tank
C. Lagoon
D. Skimming tank
Answer» B. Imhoff tank
19.

Coal mines drainage waste water (acidic in nature) results from the earth's water percolating through the voids created in coal bed during mining. This polluted water which either drains out naturally to water courses or are removed before starting the mining is

A. Neutralised by alkali treatment
B. Left as such without any treatment
C. Diluted with fresh water to reduce its acidity
D. None of these
Answer» B. Left as such without any treatment
20.

A considerable part of the harmful ultraviolet radiation of the sum does not reach the earth surface, because of the fact that, there is a layer of __________ high above earth's atmosphere, which absorbs it.

A. Hydrogen
B. Carbon dioxide
C. Ozone
D. None of these
Answer» D. None of these
21.

Presence of carbon monoxide in atmosphere produced by decomposition of chlorophyl and haemoglobin breakdown of some animals, beyond TLV (>50 ppm)

A. Acts as a green house gas thereby raising earth's temperature
B. Causes asphyxia
C. Causes increase in sea level
D. Inhances the green house effect
Answer» C. Causes increase in sea level
22.

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
23.

Reingleman chart is used for the evaluation of __________ pollution.

A. Air
B. Water
C. Noise
D. Radioactive
Answer» B. Water
24.

The permissible color for domestic water supply is __________ ppm.

A. 1
B. 20
C. 100
D. 1000
Answer» C. 100
25.

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 of the above
Answer» E.
26.

TLV of ammonia, nitrogen dioxide and phenol vapor in air is __________ ppm.

A. 5
B. 100
C. 1000
D. 2000
Answer» B. 100
27.

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
28.

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
29.

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
30.

Ethanolamine is an absorbant used for the removal of __________ from air/gas.

A. HF
B. SO₂
C. H₂S
D. Both B & C
Answer» E.
31.

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
32.

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
33.

Inhalation of silica dust causes a disease called

A. Bronchitis
B. Silicosis
C. Pneumoconiosis
D. None of these
Answer» C. Pneumoconiosis
34.

Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed by

A. Chlorination
B. Treating in biological oxygen pond
C. Chemical coagulation
D. None of these
Answer» C. Chemical coagulation
35.

5-200 μm size particles are called

A. Colloids or aerosols
B. Powder
C. Dust
D. Smoke
Answer» B. Powder
36.

Maximum permissible limit of mercury in human blood is __________ micrograms/100 c.c.

A. 1
B. 7
C. 19
D. 82
Answer» C. 19
37.

As per the world health organisation (WHO) specification, the maximum permissible concentration (i.e., TLV) of particulate matter in air is __________ μg/m³.(μg-microgram)

A. 10
B. 90
C. 800
D. 750
Answer» C. 800
38.

Reingleman chart No. 2 corresponds to __________ percent black smoke.

A. 10
B. 20
C. 40
D. 80
Answer» D. 80
39.

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.
40.

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
41.

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.
42.

Average human body contains about __________ percent water by weight.

A. 20
B. 40
C. 70
D. 85
Answer» D. 85
43.

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
44.

Out of the following, TLV of __________ is maximum (about 500 ppm).

A. Carbon dioxide
B. Toluene
C. Carbon disulphide
D. Acetaldehyde
Answer» B. Toluene
45.

In water treatment, alum[Al2(SO₄)3] is used for the process of

A. Filtration
B. Coagulation
C. Sedimentation
D. Disinfection
Answer» C. Sedimentation
46.

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
47.

Noise level audible to audience sitting in the 5th row from the stage during a large orchestra show corresponds to about __________ decibels.

A. 105
B. 135
C. 160
D. 185
Answer» C. 160
48.

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
49.

Limestone powder is injected during pulverised coal burning in boilers to __________ the flue gases.

A. Reduce SO₂ content in
B. Catalytically convert SO₂ to SO₃ in
C. Increase the dew point of
D. None of these
Answer» B. Catalytically convert SO₂ to SO₃ in
50.

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