Explore topic-wise MCQs in Environmental Engineering.

This section includes 204 Mcqs, each offering curated multiple-choice questions to sharpen your Environmental Engineering knowledge and support exam preparation. Choose a topic below to get started.

51.

The process of passing the water through a thick layer of filtering media is known as

A. Sedimentation
B. Disinfection
C. Putrification
D. Filtration
E. Purification
Answer» E. Purification
52.

In one litre sample of drinking water the coliform organism should not exceed

A. 1
B. 100
C. 10
D. 1000
E. 500
Answer» D. 1000
53.

For the maximum acidity of water, pH value would be

A. 0.1
B. 10
C. 1
D. 0.01
E. 11
Answer» E. 11
54.

Which of the following fuel has maximum resistance to detonation?

A. Toulene
B. Benzene
C. Iso-octane
D. n-heptane
E. None of the above
Answer» D. n-heptane
55.

Turbidity in water may be removed by

A. Aeration
B. Sedimentation
C. Oxidation
D. Filtration
E. Agitation
Answer» C. Oxidation
56.

Which one of the following gases shows a different behaviour at high pressure?

A. Ozone
B. Hydrogen
C. Carbon dioxide
D. Water vapours
E. None of these
Answer» C. Carbon dioxide
57.

Which one among the following terms best describes the method of converting a spherical surface into a plane surface?

A. Projection
B. Cartography
C. None of these
D. Geodesy
E. Photogrammetry
Answer» B. Cartography
58.

Bleaching power is

A. Stacked lime
B. Hypo-chloride of lime
C. Chloride of lime
D. Hypo-chlorite of lime
E. Lime
Answer» E. Lime
59.

Which of the following industry is least polluting?

A. Rolling mills
B. Oil refinery
C. Cement industry
D. Thermal power plants
E. Electronic industry
Answer» F.
60.

Which of the following constituent of air has the least percentage?

A. Helium
B. Carbon dioxide
C. Xenon
D. Neon
E. Argon
Answer» D. Neon
61.

The permissible level of HCN in drinking water is

A. More than 50 mg/litre
B. Around 1 mg/litre
C. Less than 0.01 mg/litre
D. Between 10 to 20 mg/litre
E. Around 5 mg/litre
Answer» D. Between 10 to 20 mg/litre
62.

What is a laser?

A. Electro-magnetic waves
B. Light amplification by stimulated emission of radiation
C. Supersonic waves
D. Green
E. Ultrasonic waves
Answer» C. Supersonic waves
63.

The permissible hardness of water for public supplies is

A. 400 mg/litre
B. 10 mg/litre
C. 25 mg/litre
D. 75 mg/litre
E. 115 mg/litre
Answer» F.
64.

Which of the following automobile will provide least pollution problems

A. Battery powered
B. Petrol engine powered
C. Gas turbine powered
D. Diesel engine powered
E. Wankel engine powered
Answer» B. Petrol engine powered
65.

To keep the water safe against pathogenetic bacteria the residual chlorine should remain between

A. 10 ppm to 20 ppm
B. 1 ppm to 2 ppm
C. 0.2 to 0.8 ppm
D. 0.05 to 0.2 ppm
E. 6 ppm to 10 ppm
Answer» E. 6 ppm to 10 ppm
66.

The most frequent method of bacterial reproduction is by

A. The formation of spores
B. Budding
C. Cell division
D. Colony formation
E. Sexual process
Answer» D. Colony formation
67.

Bit is the unit of

A. Quantity of electricity
B. Intensity of an earthquake
C. None of these
D. Memory of computer
E. Amount of rain recorded
Answer» E. Amount of rain recorded
68.

Disinfection of drinking water means removal of

A. Bacteria
B. Colour
C. Odour
D. Turbidity
E. Oxygen
Answer» B. Colour
69.

What will be the colour of red rose when it is seen through green glass?

A. Pink
B. White
C. Brown
D. Green
E. Black
Answer» D. Green
70.

Which of the following chemical is least poisonous?

A. Mercury
B. Cyanide
C. Arsenic
D. Lead
E. Sodium
Answer» F.
71.

The permissible hardness of water for low pressure boiler is

A. 150 mg/litre
B. 50 mg/litre
C. 350 kg/litre
D. 250 mg/litre
E. 450 mg/litre
Answer» C. 350 kg/litre
72.

The percentage of nitrogen in air by weight is around

A. 24.3 percent
B. 23.1 percent
C. 65.5 percent
D. 75.5 percent
E. 20.3 percent
Answer» E. 20.3 percent
73.

The chloride content in the water for public supplies should not exceed

A. 1 mg/litre
B. 250 mg/litre
C. 50 mg/litre
D. 20 mg/litre
E. 100 mg/litre
Answer» C. 50 mg/litre
74.

The odour of water is expressed in terms of threshold number. The maximum threshold number permitted for public supplies is

A. 10
B. 1
C. 2
D. 5
E. 3
Answer» F.
75.

Identify the incorrect statement if any Zeolite process is suitable for

A. When zeolite becomes inactive, it may be reactivated by flushing with brine solution
B. Removing temporary hardness
C. Removing permanent hardness
D. Acidic waters
E. Cent percent removal of hardness
Answer» E. Cent percent removal of hardness
76.

The pH value of sea water is usually

A. Between 3 and 5
B. 1
C. Between 8 and 8.3
D. Between 13.7 and 14
E. Between 5 and 7
Answer» D. Between 13.7 and 14
77.

Dark, black smoke from diesel engines usually results when engine is

A. Running at light loads
B. Running at slow speeds
C. Running at full load and full speed
D. Idling
E. Running at full speed but under load conditions
Answer» D. Idling
78.

The hardness limit for portable water ranges between

A. 10 - 50 ppm
B. 300 - 700 ppm
C. 75 - 117 ppm
D. 150 - 250 ppm
E. 50 - 65 ppm
Answer» D. 150 - 250 ppm
79.

Which one of the following is not directly related to the phenomenon of evaporation?

A. Temperature of liquid
B. Volume of the liquid
C. Surface area of the liquid
D. Surface winds over the liquid
E. None of these
Answer» C. Surface area of the liquid
80.

Which of the following is a cold cathode lamp?

A. Sodium vapour lamp
B. High pressure mercury vapour lamp
C. Low pressure mercury vapour lamp
D. Neon lamp
E. None of the above
Answer» E. None of the above
81.

Which pollutants result from automobile exhaust?

A. Carbon monoxide
B. Nitrous oxide
C. Hydrocarbons
D. Sulphur dioxide
E. All of the above
Answer» F.
82.

A fuel of octane rating 85 matches the antiknock qualities of a mixture consisting of

A. 85% petrol + 15% diesel
B. 15% petrol + 85% diesel
C. 85% benzene + 15% methyl chloride
D. 85% octane + 15% heptane
E. None of the above
Answer» E. None of the above
83.

For controlling the growth of algae, the chemical generally used is

A. Alum
B. Lime
C. Bleaching powder
D. Copper sulphate
E. Ozone
Answer» E. Ozone
84.

Corrosive action of water could be due to its

A. alkalinity
B. hardness
C. dissolved oxygen
D. Any of the above
E. None of the above
Answer» E. None of the above
85.

Which of the following shading device will transmit least leat inside a room?

A. Plain glass sheet 3 mm thick
B. Plain glass sheet with wire mesh outside
C. Plain glass sheet with Venetion blind inside
D. Plain glass with curtain inside
E. None of the above
Answer» E. None of the above
86.

Which of the following can have octane rating of more than 100?

A. Gobar gas
B. Methyl alcohol
C. Benzol
D. Ethyl alcohol
E. None of the above
Answer» D. Ethyl alcohol
87.

The desirable temperature inside an air conditioned auditorium is

A. 0?C
B. 5?C
C. 10?C
D. 20?C
E. None of the above
Answer» E. None of the above
88.

The speed of sound through human body is around

A. 344 m/s
B. 688 m/s
C. 1560 m/s
D. 3120 m/s
E. None of the above
Answer» D. 3120 m/s
89.

Which of the following engines uses two fuels simulataneously?

A. Multifuel engine
B. Wankel engines
C. Free piston gas generator
D. Dual fuel engines
E. None of the above
Answer» E. None of the above
90.

All of the following pollutants are produced as a result of decaying organic matter EXCEPT

A. Ammonia
B. Sulphur dioxide
C. Methane
D. Hydrogen sulphide
E. None of the above
Answer» C. Methane
91.

The flouride content in the drinking water should not exceed

A. 200 mg/litre
B. 150 mg/litre
C. 100 mg/litre50 mg/litre
D. 50 mg/litre
E. 1 mg/litre
Answer» F.
92.

The anitdote for the poisonous effects due to mercury, is

A. Vitamin K
B. BAL
C. Thiosulphate
D. Altropine
E. Any of the above
Answer» C. Thiosulphate
93.

Out of the following metals the least permissible percentage in drinking water is

A. Chromium
B. Copper
C. Zinc
D. Lead
E. None of the above
Answer» B. Copper
94.

On board ships, the source of drinking water may be

A. Rain water
B. Sea water
C. Desalted sea water
D. Pumped deep sea water
E. Any of the above
Answer» D. Pumped deep sea water
95.

Which thermometer is used to indicate the lowest temperature?

A. Clinical thermometer
B. Alcohol thermometer
C. Resistance thermometer
D. Liquid thermometer
E. Green
Answer» C. Resistance thermometer
96.

The first aid for a victim of electric shock is

A. bandage
B. sprinkling of water on the face
C. glass of milk and cold water
D. artificial respiration
E. None of the above
Answer» E. None of the above
97.

Prechlorination

A. Improves coagulation
B. Reduces odours
C. Reduces organisms
D. All of the above
E. None of the above
Answer» F.
98.

In the jet propulsion, efficiency of the propulstion depends upon

A. The speed of the vehicle
B. Height at which the vehicle is travelling
C. Density of the medium in which the vehicle is travelling
D. All of the above
E. Green
Answer» D. All of the above
99.

The unit parts per million is identical to

A. Grains per galleon
B. Pounds per cubic foot
C. Milligrams per kg
D. Tonnes peracre foot
E. None of the above
Answer» D. Tonnes peracre foot
100.

If with minimum quantity of potassium permanganate, the pink colour of water disappears soon, then it shows that

A. Water is hard
B. Water is acidic
C. Chlorine content is high in water
D. Water is alkaline
E. Organic matter is present in water
Answer» F.