Explore topic-wise MCQs in Chemical Engineering.

This section includes 444 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

Very small amount of air pollutants are present in stratosphere also; though most of the atmospheric pollutants are present in the troposphere. Which of the following atmospheric pollutants does not cause the ozone layer depletion in atmosphere at tremendous rate?

A. O
B. O₂
C. Ox
D. FC (chloro fluoro carbons)
Answer» B. O₂
2.

'Particulate' air pollutants are finely divided solids and liquids. Which of the following is not a 'particulate'?

A. ust & mists
B. moke & fumes
C. hotochemical smog & soot
D. one of these
Answer» E.
3.

Which of the following is the most efficient for removal of very finely divided suspended solids and colloidal matter from the polluted water stream?

A. edimentation tank
B. ircular clarifier
C. echanical flocculation
D. hemical coagulation
Answer» E.
4.

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. 00
B. 000
C. 00
D. 000
Answer» C. 00
5.

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.
B. 0⁵
C. 0⁹
D. 0¹⁵
Answer» C. 0⁹
6.

BOD of raw municipal sewage may be in the range of about __________ mg/litre.

A. 1-2
B. 5-10
C. 150-300
D. 2000-3000
Answer» D. 2000-3000
7.

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
8.

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
9.

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
10.

__________ content of the phosphate rock is the pollutant of primary interest in a phos-phatic fertiliser plant.

A. Calcium
B. Fluorine
C. Phosphorous
D. Sulphur
Answer» C. Phosphorous
11.

Most of the bacteria in sewage are

A. Parasitic
B. Saprophytic
C. Anerobic
D. None of these
Answer» C. Anerobic
12.

The lowest layer of atmosphere is known as the

A. Stratosphere
B. Troposphere
C. Ionosphere
D. None of these
Answer» C. Ionosphere
13.

Which of the following is the most lethal water pollutant?

A. Phenol and cynide
B. Chlorine
C. Alkalis
D. Suspended solids
Answer» B. Chlorine
14.

Waste/polluted water discharged from electroplating, blast furnace and coal mining industries contain mainly __________ substances.

A. Radioactive
B. Organic
C. Inorganic
D. None of these
Answer» D. None of these
15.

A standard test for determination of hardness in water is termed as __________ test.

A. EDTA
B. Electometric
C. Total count
D. Presumptive
Answer» B. Electometric
16.

TLV of aldrin in public water supply system is about __________ μg/litre.

A. 0.5
B. 17
C. 357
D. 1097
Answer» C. 357
17.

Presence of nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N₂ in contaminated air at which it acts as a natural asphyxant is ≥ __________ percent.

A. 84
B. 88
C. 80
D. 92
Answer» B. 88
18.

Higher concentration of nitrogen dioxide in atmospheric air causes

A. Cancer
B. Bronchitis
C. Asphyxiation
D. Corrosion
Answer» C. Asphyxiation
19.

Presence of excess flourine in water causes

A. Dental cavity
B. Tooth decay
C. Fluorosis
D. Respiratory disease
Answer» D. Respiratory disease
20.

Which of the following is not an air pollutant?

A. Ozone
B. Carcinogens
C. Pesticides
D. Metallic powders
Answer» B. Carcinogens
21.

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
22.

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
23.

TLV of mercury in potable (drinking) water is about __________ ppm.

A. 0.001
B. 0.1
C. 1
D. 5
Answer» B. 0.1
24.

Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid ilow control. It is caused due to

A. Reynold stresses
B. Shear forces
C. Both A & B
D. Neither A nor B
Answer» D. Neither A nor B
25.

A gas is termed as non-toxic, if its maximum permissible concentration (TLV) ranges from __________ ppm.

A. 1000 to 2000
B. 3000 to 6000
C. 6000 to 9000
D. 10000 to 100000
Answer» E.
26.

Which of the following is the most detrimental for water used in high pressure boiler?

A. Silica
B. Turbidity
C. Phenol
D. Dissolved oxygen
Answer» B. Turbidity
27.

Noise level in a quiet private business office is about __________ decibels.

A. 25
B. 50
C. 70
D. 85
Answer» C. 70
28.

Noise level inside a jet air liner in normal flight is about __________ decibels.

A. 80
B. 100
C. 125
D. 145
Answer» C. 125
29.

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
30.

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
31.

The common pollutant generated in chlor-alkali industry and battery manufacture is

A. Mercury
B. Brine
C. Phosphate
D. None of these
Answer» B. Brine
32.

Which of the following acts as a natural source of air pollution?

A. Forest fire
B. Deforestation
C. Volcanic eruption
D. None of these
Answer» D. None of these
33.

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

A. Respirtory ailments (e.g. bronchitis)
B. Skin diseases (e.g. dermatities)
C. Silicosis
D. Blurred vision
Answer» C. Silicosis
34.

The pH value of oxidised sewage is about

A. 1.8
B. 6.2
C. 7.3
D. 13.4
Answer» D. 13.4
35.

Presence of nitrates in water in excess of 50 ppm causes

A. Mathenoglobenemia
B. Gastroentetitis
C. Asphyxiation
D. Tooth decay
Answer» B. Gastroentetitis
36.

Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off by

A. Quenching of hot coke
B. Discharging in the river stream
C. Filtration and recycling for cooling coke oven gas
D. None of these
Answer» B. Discharging in the river stream
37.

Maximum permissible turbidity in potable water is __________ ppm.

A. 1
B. 10
C. 250
D. 1000
Answer» C. 250
38.

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
39.

__________ can not control the noise pollution.

A. Use of silencers
B. Green house gases
C. Vibration damping
D. Tree plantation
Answer» C. Vibration damping
40.

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
41.

Workers working in __________ industry are most prone to white lung cancer.

A. Coal mining
B. Limestone mining
C. Textile
D. Asbestos
Answer» D. Asbestos
42.

What are the methods of treatment & disposal of radioactive wastes?

A. Evaporation & chemical precipitation
B. Biological methods & adsorption in ion exchange materials
C. Fixing into a solid mass with cement and sinking deep in the sea
D. All of the above
Answer» E.
43.

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.
44.

Smoke is produced due to

A. Insufficient supply of combustion air and insufficient time for combustion
B. Poor quality of fuel and improper mixing of fuel & combustion air
C. Poor design & overloading of furnace
D. All of the above
Answer» E.
45.

Smog is

A. Nothing but black smoke
B. A combination of smoke and fog
C. A liquid particle resulting from vapor condensation
D. A solid particle e.g. flyash
Answer» C. A liquid particle resulting from vapor condensation
46.

Carbonaceous particles having size less than 1 μm are called

A. Grit
B. Aggregates
C. Aerosols
D. Smoke
Answer» E.
47.

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
48.

Fresh domestic sewage is __________ in color.

A. Grey
B. Dark brown
C. Red
D. Black
Answer» B. Dark brown
49.

Soluble silica present in boiler feed water can be removed by

A. Coagulation
B. Filtration
C. Anion exchanger
D. Preheating it
Answer» D. Preheating it
50.

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