Explore topic-wise MCQs in Chemical Engineering.

This section includes 227 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

151.

Infective bacteria in water is killed by the _____________ process?

A. Sterilisation
B. Aeration
C. Disinfection
D. None of these
Answer» B. Aeration
152.

Industrial workers working in leather tanning & manufacturing units are prone to suffer from ___________________?

A. Respiratory ailments (e.g. bronchitis)
B. Skin diseases (e.g. dermatitis)
C. Silicosis
D. Blurred vision
Answer» C. Silicosis
153.

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
154.

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

A. Filtration
B. Coagulation
C. Sedimentation
D. Disinfection
Answer» C. Sedimentation
155.

In troposphere (the weather domain), the temperature ‘t’ at height ‘h’ above the spa level in metres is given by (where, temperature at sea level is 15°C and t is in °C ?

A. t = 15 – 0.0065h
B. t = 15 + 0.0065h
C. t = 0.0035h -15
D. t = 15 – 0.0035h
Answer» B. t = 15 + 0.0065h
156.

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
157.

In sewage treatment, the detention period allowed for oxidation ponds ranges from _____________ weeks?

A. 1 to 2
B. 4 to 5
C. 9 to 10
D. 15 to 20
Answer» C. 9 to 10
158.

In sewage treatment, its sedimentation is speeded up by commonly adding__________________?

A. Hydrochloric acid
B. Lime
C. Copper sulphate
D. Sodium sulphate
Answer» C. Copper sulphate
159.

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
160.

In a sedimentation tank, the detention period for water ranges from _____________ hours?

A. 2 to 4
B. 8 to 12
C. 16 to 20
D. 24 to 32
Answer» B. 8 to 12
161.

Hydrogen ion concentration in distilled water is___________________?

A. 10-7
B. 7 × 10-7
C. 107
D. 7 × 107
Answer» B. 7 × 10-7
162.

Higher concentration of nitrogen dioxide in atmospheric air causes___________________?

A. Cancer
B. Bronchitis
C. Asphyxiation
D. Corrosion
Answer» C. Asphyxiation
163.

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.
164.

High noise levels produced during operation of fans and compressors can be reduced by using__________________?

A. Mufflers (silencers)
B. Acoustic absorbent
C. Lagging of noisy duct
D. None of these
Answer» B. Acoustic absorbent
165.

High noise level in a chemical plant can be controlled by the_________________?

A. Suppression of noise at the source itself
B. Path control of noise
C. Protection of operating personnel
D. All A., B. & C.
Answer» E.
166.

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
167.

Hazardous/polluting chemical industries should have an ‘exclusion zone’ with a green belt and general public access prohibited around it, covering a radius of _____________ metres?

A. 100
B. 1000
C. 400
D. 4000
Answer» C. 400
168.

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
169.

Growth of ______________ is promoted by the presence of manganese in water?

A. Files
B. Algae
C. Micro-organisms
D. Mosquitoes
Answer» D. Mosquitoes
170.

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
171.

Green house effect is accentuated by________________?

A. Deforestation
B. Rapid industrialisation
C. Increased transportation activity
D. All A., B. and C.
Answer» E.
172.

Global warming may result in __________________?

A. Flood
B. Cyclone
C. Decrease in food productivity
D. All A., B. and C.
Answer» E.
173.

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

A. 5
B. 50
C. 500
D. 5000
Answer» B. 50
174.

Fresh sewage is ______________ in nature?

A. Acidic
B. Neutral
C. Alkaline
D. Highly acidic
Answer» D. Highly acidic
175.

Fresh domestic sewage is _______________ in color?

A. Grey
B. Dark brown
C. Red
D. Black
Answer» B. Dark brown
176.

Foul odour and bad taste of water is removed by treating with__________________?

A. Alum
B. Bleaching powder
C. Activated carbon
D. Copper sulphate
Answer» D. Copper sulphate
177.

For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than ______________ ppm?

A. 10000
B. 5
C. 500
D. 1000
Answer» C. 500
178.

Foaming and priming in boiler operation can be reduced by reduction in ______________ in feed water?

A. Turbidity
B. Color (Hazen)
C. Total solids
D. All A., B. & C.
Answer» E.
179.

Fluorosis is caused due to the presence of excessive amount of ______________ in drinking water?

A. Mercury
B. Lead
C. Fluoride
D. Arsenic
Answer» D. Arsenic
180.

Fluorosis (a bone disease) is caused by the presence of high concentration of ____________ in atmospheric air?

A. Hydrocarbons
B. Hydrogen fluoride
C. Hydrogen sulphides
D. Nitrogen dioxide
Answer» C. Hydrogen sulphides
181.

Fine grit present in sewage is removed in the _____________ during sewage treatment?

A. Grit chamber
B. Detritus tank
C. Trickling filter
D. Skimming tank
Answer» C. Trickling filter
182.

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
183.

Exposure to SO2 containing chimney gases results in the__________________?

A. Reduction in strength of leather & cloth
B. Acceleration of corrosion rates of metals
C. Increased drying & hardening time of paints
D. All A., B. and C.
Answer» E.
184.

Exposure to chemicals having carcinogenic properties cause___________________?

A. Dermatitis (skin disorder)
B. Cancer
C. Asphyxiation
D. Asthma
Answer» C. Asphyxiation
185.

Exposure to chemicals having carcinogenic properties cause ____________________?

A. Dermatitis (skin disorder)
B. Cancer
C. Asphyxiation (suffocation)
D. Asthma
Answer» C. Asphyxiation (suffocation)
186.

Ethanolamine is an absorbent used for the removal of _____________ from air/gas?

A. HF
B. SO2
C. H2S
D. Both B. & C.
Answer» E.
187.

Dust collection efficiency of a cyclone separator depends upon its______________?

A. Diameter
B. Inlet gas velocity
C. Overall height
D. All A., B. & C.
Answer» E.
188.

During sewage treatment, the sewage is subjected to ______________ treatment in Imhoff tank?

A. Filtration
B. Digestion
C. Sedimentation
D. Both B. and C.
Answer» E.
189.

Dissolved oxygen content in river water is around _____________ ppm?

A. 5
B. 100
C. 250
D. 500
Answer» B. 100
190.

Disinfection of water is done to remove ______________________?

A. Color
B. Bad taste
C. Foul odour
D. Bacteria
Answer» E.
191.

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.
192.

Direct reaction of unsaturated hydrocarbons with either NO or NO2 produces an eye irritating pollutant compound known as________________?

A. Photochemical smog
B. Peroxyacetyl nitrate (PAN) or methyl nitrite
C. Benzopyrene
D. Polyacrylonitrile
Answer» C. Benzopyrene
193.

Death may occur, when SO2 concentration in atmospheric air exceeds ______________ ppm?

A. 20
B. 100
C. 400
D. 200
Answer» D. 200
194.

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
195.

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.
196.

______________ content of the phosphate rock is the pollutant of primary interest in a phosphatic fertiliser plant ?

A. Calcium
B. Fluorine
C. Phosphorous
D. Sulphur
Answer» C. Phosphorous
197.

Color test of water is done with an instrument called__________________?

A. Tintometer
B. Colorimeter
C. Electro-chemical cell
D. Turbidimeter
Answer» B. Colorimeter
198.

COD of raw municipal sewage may be in the range of about _____________ mg/litre?

A. 1-2
B. 5-10
C. 90-120
D. 1500-2500
Answer» D. 1500-2500
199.

Coal washing waste water containing about 3% suspended solids (comprising of clay, slate, stone etc.) is treated for solid particles removal ?

A. By chemical coagulation
B. In sedimentation tanks equipped with mechanical scrapper
C. In vacuum filter
D. In clarifiers
Answer» C. In vacuum filter
200.

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 ozone?

A. 102
B. 105
C. 109
D. 1015
Answer» C. 109