Explore topic-wise MCQs in Chemical Engineering.

This section includes 528 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.

Beyond what concentration of HS in air, acute danger to human life exists ?

A. 50 ppm
B. 100 ppm
C. 300 ppm
D. 700 ppm
Answer» E.
2.

TLV of NO & NO exposure for the human being is 5 & 25 ppm respectively. Prolonged exposure of human being to NO causes

A. skin disorder
B. bronchitis
C. bone disease
D. cancer
Answer» C. bone disease
3.

Exposure to SO 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.
4.

Which of the following plants does not emit appreciable amount of SO in atmosphere ?

A. Thermal power plant
B. Petroleum refinery
C. Nitric acid plant
D. Sulphuric acid plant
Answer» D. Sulphuric acid plant
5.

The maximum CO is emitted into the atmosphere by

A. combustion
B. urea
C. biomass burning
D. trees
Answer» B. urea
6.

In water treatment, alum[Al(SO)] is used for the process of

A. filtration
B. coagulation
C. sedimentation
D. disinfection
Answer» C. sedimentation
7.

Nitrogen oxides (NO) is not produced in the __________ industry.

A. nitric acid making
B. nitrogenous fertiliser
C. detergent
D. any of these
Answer» D. any of these
8.

Which of the following radioactive wastes emits all α, β & γ rays and hence is the most hazardous of all radioactive emitters?

A. I-131
B. Sr-90
C. Au-198
D. Ra-226
Answer» E.
9.

Acute danger to human life (i.e. death) exists, if the concentration of CO in atmospheric air exceeds __________ percent (by volume).

A. 1
B. 3
C. 7
D. 20
Answer» E.
10.

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

A. grit
B. dust
C. powder
D. smoke
Answer» B. dust
11.

Water filtration rate in a rapid sand filter ranges from __________ kilolitres/m/hr.

A. 0.1 to 1
B. 3 to 6
C. 10 to 15
D. 15 to 20
Answer» C. 10 to 15
12.

Water filtration rate in a slow sand filter ranges from __________ litres/m/hr.

A. 10 to 20
B. 100 to 200
C. 1500 to 2500
D. 4000 to 5000
Answer» C. 1500 to 2500
13.

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 N in contaminated air at which it acts as a natural asphyxant is ≥ __________ percent.

A. 84
B. 88
C. 80
D. 92
Answer» B. 88
14.

__________ plant emits large amount of SO as an air pollutant.

A. Nitric acid
B. Sulphuric acid
C. Chloralkali
D. Iron & steel
Answer» C. Chloralkali
15.

Which of the following is an adsorbant used for the removal of SO from gas/air ?

A. Bog iron
B. Limestone powder or alkalised alumina
C. Silica gel
D. Active carbon
Answer» C. Silica gel
16.

Carbonaceous particles having size less than 1 μm are called

A. grit
B. aggregates
C. aerosols
D. smoke
Answer» E.
17.

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

A. 0.5
B. 17
C. 357
D. 1097
Answer» C. 357
18.

When the concentration of SO in air is greater than __________ ppm, it gives a pungent smell.

A. 0.01
B. 0.1
C. 1
D. 4
Answer» E.
19.

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

A. 10
B. 90
C. 800
D. 750
Answer» C. 800
20.

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

A. photochemical smog.
B. peroxy acetyl nitrate (PAN) or methyl nitrile.
C. benzopyrene.
D. poly acrylonitrile
Answer» C. benzopyrene.
21.

Which of the following is a green house gas other than CO ?

A. Methane
B. Nitrous oxide
C. Chlorofluro carbons (CFC)
D. All (a), (b) and (c)
Answer» E.
22.

In troposphere (the weather domain), the temperature '' at height '' above the spa level in metres is given by (where, temperature at sea level is 15°C and is in °C.)

A. = 15 - 0.0065
B. = 15 + 0.0065
C. = 0.0035
D. -15
E. = 15 - 0.0035
Answer» B. = 15 + 0.0065
23.

Death may occur, when SO concentration in atmospheric air exceeds __________ ppm.

A. 20
B. 100
C. 400
D. 200
Answer» D. 200
24.

Higher concentration of CO 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.
25.

TLV of ozone (O) and phosgene (COCl) in air is __________ ppm.

A. 0.1
B. 25
C. 100
D. 1000
Answer» B. 25
26.

HS 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
27.

Threshold Limit Value (TLV) is the maximum allowable concentration (i.e. safe limit) of pollutants in air. Safe limit for SO in air is __________ ppm.

A. 5
B. 500
C. 1000
D. 2000
Answer» B. 500
28.

Maximum allowable concentration of CO in air for safe working is __________ ppm (parts per million).

A. 50
B. 1000
C. 2000
D. 5000
Answer» E.
29.

Which of the following is represented b the green curve in the above figure?

A. deoxygenation curve
B. reoxygenation curve
C. oxygen sag curve
D. equilibrium concentration of oxygen
Answer» C. oxygen sag curve
30.

In which type of settling, settling of particles takes place by the contact of impurities with each other present inwastewater?

A. flocculent settling
B. hindered settling
C. compression settling
D. discrete settling
Answer» D. discrete settling
31.

is the velocity at which the solid matter in sewage remained in suspended form.

A. settling velocity
B. self cleansing velocity
C. mean velocity
D. non scouring velocity
Answer» C. mean velocity
32.

Which of the following device is used for the removal of oil and grease?

A. skimming tank
B. grit chambers
C. tube settlers
D. flocculator
Answer» B. grit chambers
33.

Screens are inclined to the direction offlow to

A. increase the flowvelocity
B. increase theopening area
C. decrease theflow velocity
D. increase the headloss
Answer» D. increase the headloss
34.

The wet weather flow is also known by

A. minimum sewageflow
B. maximum sewageflow
C. storm waterflow
D. average rate offlow
Answer» D. average rate offlow
35.

How many types of aerators are commonly used in the treatment ofwastewater?

A. 2
B. 3
C. 4
D. 5
Answer» B. 3
36.

How is mixing done in SBR?

A. manual
B. mechanical
C. air stripping
D. agitation by air
Answer» C. air stripping
37.

The design velocity of flow of adetritus tank is

A. 1m/sec
B. 1.2m/sec
C. 0.9m/sec
D. 0.5m/sec
Answer» D. 0.5m/sec
38.

Which system of collection of sewageis a dry system?

A. conservancysystem
B. biologicaldigestion
C. incernation
D. water carriagesystem
Answer» B. biologicaldigestion
39.

What is yellow curve represents in the following figure?

A. deoxygenation curve
B. reoxygenation curve
C. oxygen sag curve
D. equilibrium concentration of oxygen
Answer» B. reoxygenation curve
40.

In which type of settling, sedimentation of discrete particlestakes place?

A. zone settling
B. compression settling
C. hindered settling
D. discrete settling
Answer» E.
41.

Which of the following process is not adopted in oxidation ditches?

A. adsorption
B. desorption
C. oxidation
D. decomposition
Answer» C. oxidation
42.

Which reactors are characterized by non- continuous reactions?

A. plug flow reactor
B. continuous reactor
C. batch reactor
D. fluidized bed reactor
Answer» D. fluidized bed reactor
43.

What is the minimum depth of water to be kept in the oxidation pond?

A. 0.3m
B. 0.5m
C. 1 m
D. 1.5m
Answer» D. 1.5m
44.

The average time required by water to pass through the settling tank is called

A. detention time
B. flow through period
C. time of flow
D. mean time
Answer» C. time of flow
45.

is the flow through sewers available during non-rainfall period.

A. gradually varied flow
B. rapidly varied flow
C. dry weather flow
D. storm water flow
Answer» D. storm water flow
46.

The maximum size of filter media of apercolating filter is

A. 10mm
B. 25mm
C. 60mm
D. 75mm
Answer» E.
47.

is the ratio of volume of recirculated sewage to the raw sewage.

A. recirculation factor
B. recirculation ratio
C. food to mass ratio
D. bod
Answer» C. food to mass ratio
48.

The recirculation ratio for the low ratetrickling filter is

A. 1
B. 2
C. 3
Answer» E.
49.

is the additional flowoccurring during rainy season.

A. gradually variedflow
B. rapidly variedflow
C. dry weatherflow
D. storm waterflow
Answer» E.
50.

The size of filter media in a high ratetrickling filter is

A. 10-20mm
B. 34-68mm
C. 25-60mm
D. 20-50mm
Answer» D. 20-50mm