Explore topic-wise MCQs in Chemical Engineering.

This section includes 362 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.

Which of the following terminology is not used for size reduction of materials to fine sizes or powders ?

A. Comminution
B. Dispersion
C. Pulverisation
D. Compression
Answer» E.
2.

Width and speed of a conveyor belt depends upon the ______________ of the material?

A. Lump size
B. Bulk density
C. Both A. & B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
3.

With increase in drum speed, in a rotary drum filter, the filtration rate_______________?

A. Increases
B. Increases linearly
C. Decreases
D. Is not affected
Answer» B. Increases linearly
4.

With increase in the capacity of screens, the screen effectiveness__________________?

A. Remains unchanged
B. Increases
C. Decreases
D. Decreases exponentially
Answer» D. Decreases exponentially
5.

With increase in the pressure drop across the cake, the specific cake resistance for the compressible sludge________________?

A. Increases
B. Decreases
C. Remains constant
D. Increases linearly
Answer» B. Decreases
6.

Work index is defined as the_________________?

A. Gross energy (kWh/ton of feed) needed to reduce very large feed to such a size that 80% of the product passes through a 100 micron screen
B. Energy needed to crush one tonne of feed to 200 microns
C. Energy (kWh/ton of feed) needed to crush small feed to such a size that 80% of the product passes a 200 mesh screen
D. Energy needed to crush one ton of feed to 100 microns
Answer» B. Energy needed to crush one tonne of feed to 200 microns
7.

Work index is the gross energy (kWh/tonne of feed) necessary to reduce a very large feed to such a size that 80% of product particles will pass through a 0.1 mm screen. The value of work index determined for wet grinding should be multiplied with ______________ to get the same for dry grinding?

A. 1.0
B. 0.5
C. 1.34
D. 4.34
Answer» D. 4.34
8.

Xanthates are used in the froth floatation process as a/an _______________________?

A. Conditioner
B. Frother
C. Collector
D. Activator
Answer» D. Activator
9.

Which of the following relationships between co-efficient of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct ?

A. μ > tan α
B. μ ≥ tan α
C. μ > tan 2α
D. μ ≤ tan α
Answer» C. μ > tan 2α
10.

Which of the following oxides is not present in hematite iron ore ?

A. Titanium oxide
B. Calcium oxide
C. Cobalt oxide
D. Manganese oxide
Answer» D. Manganese oxide
11.

Which of the following minerals is not subjected to magnetic separation method ?

A. Rutile
B. Galena
C. Chromite
D. Siderite
Answer» C. Chromite
12.

Which of the following mineral dressing operations is termed as ‘comminution’?

A. Panning
B. Spiralling
C. Tabling
D. None of these
Answer» E.
13.

Which of the following mechanical conveyors does not come under the division „carriers‟ ?

A. Belt conveyor
B. Bucket elevator
C. Screw conveyor
D. Apron conveyor
Answer» D. Apron conveyor
14.

Which of the following mechanical conveyors does not come under the division „scrapers‟ ?

A. Ribbon conveyor
B. Flight conveyor
C. Bucket elevators
D. Drag conveyor
Answer» D. Drag conveyor
15.

Which of the following is not used as filter aid ?

A. Asbestos
B. Diatomaceous earth
C. Purified wood cellulose
D. Rice husk
Answer» E.
16.

Which of the following is not used as a surface active agent in a flocculation operation ?

A. Sodium silicate
B. Quartz
C. Lime
D. Alumina
Answer» C. Lime
17.

Which of the following is not categorised as a “mechanical operation”?

A. Agitation
B. Filtration
C. Size enlargement
D. Humidification
Answer» E.
18.

Which of the following is not an ultrafine grinder (colloid mill) ?

A. Micronizers
B. Agitated mills and fluid energy mills
C. Toothed roll crusher
D. Hammer mills with internal classification
Answer» D. Hammer mills with internal classification
19.

Which of the following is not accomplished by agitation of liquids in agitators ?

A. Dispersing gas in liquid
B. Blending of immiscible liquids
C. Dispersing immiscible liquid in form of emulsion
D. Suspending solid particles
Answer» C. Dispersing immiscible liquid in form of emulsion
20.

Which of the following is not a revolving/tumbling mill used for size reduction ?

A. Compartment mill
B. Pebble mill
C. Cage mill
D. Rod mill
Answer» D. Rod mill
21.

Which of the following is not a part of the Blake jaw crusher ?

A. Hanger
B. Check plates
C. Toggles
D. Pitman
Answer» B. Check plates
22.

Which of the following is not a non-metalliferous mineral ?

A. Calcite
B. Fluorspar
C. Quartz
D. Cassiterite
Answer» E.
23.

Which of the following is not a cutting machine ?

A. Dicers
B. Knife cutters
C. Slitters
D. Tube mills
Answer» E.
24.

Which of the following is a fine crusher ?

A. Blake jaw crusher
B. Gyratory crusher
C. Toothed roll crusher
D. Dodge jaw crusher
Answer» D. Dodge jaw crusher
25.

Which of the following is a continuous filter ?

A. Plate and frame filter
B. Cartridge filter
C. Shell and leaf filter
D. None of these
Answer» E.
26.

Which of the following is a coarse crusher ?

A. Smooth roll crusher
B. Toothed roll crusher
C. Gyratory crusher
D. Tube mill
Answer» D. Tube mill
27.

Which of the following gives the work required for size reduction of coal to -200 mesh in a ball mill most accurately?

A. Rittinger’s law
B. Kick’s law
C. Bond’s law
D. None of these
Answer» B. Kick’s law
28.

Which of the following equations is Rittinger’s crushing law? (Where P = power required by the machine, m = feed rate, k = a constant, D̅ sa & D̅ sb = volume surface mean diameter of feed & product respectively) ?

A. P/m = K/ √Dp
B. P/m = K . ln D̅ sa/D̅ sb
C. P/m = K . (1/ D̅ sb – 1/D̅ sa)
D. None of these
Answer» D. None of these
29.

Which of the following clay mixing devices is vacuum operated for deairation of clay ?

A. Banbury mixer
B. Pug mill
C. Muller-mixer
D. None of these
Answer» C. Muller-mixer
30.

Which of the following can be most effectively used for clarification of lube oil and printing ink ?

A. Sparkler filter
B. Pre-coat filter
C. Disc-bowl centrifuge
D. Sharpies super-centrifuge
Answer» E.
31.

Which of the following agitators having a large blade area, rotating at slow speed is used for mixing high viscosity liquids (> 50000 centipoise) ?

A. Propeller
B. Helical screw
C. Flat blade turbine
D. Curved blade turbine
Answer» C. Flat blade turbine
32.

Which of the following achieves the least reduction ratio for a given feed size ?

A. Jaw crusher
B. Roll crusher
C. Cone crusher
D. Gyratory crusher
Answer» C. Cone crusher
33.

Where the density difference of the two liquid phase to be separated is very small (as in milk cream separator), the most suitable separator is a____________________?

A. Disc bowl centrifuge
B. Sharpies super-centrifuge
C. Batch basket centrifuge
D. Sparkler filter
Answer» B. Sharpies super-centrifuge
34.

Wheat is ground into flour in a___________________?

A. Hammer crusher
B. Roller crusher
C. Impact mill
D. Fluid energy mill
Answer» C. Impact mill
35.

What is the reduction ratio in a fine crushing operation having following feed and product sizes ?

A. 0.5
B. 2
C. 5
D. 10
Answer» C. 5
36.

Wet sieving is employed, when the product contains ________________ materials?

A. Abrasive
B. Large quantity of very fine
C. Coarse
D. Non-sticky
Answer» C. Coarse
37.

Wet grinding in a revolving mill ______________ as compared to dry grinding ?

A. Gives less wear on chamber walls
B. Requires more energy
C. Increases capacity
D. Complicates handling of the product
Answer» D. Complicates handling of the product
38.

Weber number is significant and is concerned with the_________________?

A. Solid-liquid mixing
B. Liquid-liquid mixing
C. Dispersion of liquid in liquid
D. Suspension of solid in liquid
Answer» D. Suspension of solid in liquid
39.

Washability curve based on float and sink test enables an assessment to be made of the possibility of cleaning a coal fraction based on the____________________?

A. Density separation
B. Differential wettability
C. Size
D. Volatile matter content
Answer» B. Differential wettability
40.

Vibrating screens have capacity in the range of ______________ tons/ft2 .mm mesh size?

A. 0.2 to 0.8
B. 5 to 25
C. 50 to 100
D. 100 to 250
Answer» B. 5 to 25
41.

Vibrating screens are used for handling large tonnages of materials. The vibrating motion is imparted to the screening surface by means of_____________________?

A. Electromagnets
B. Cams or eccentric shafts
C. Unbalanced flywheels
D. Either A., B. or C.
Answer» E.
42.

Vertical transportation of materials can be done by a/an_______________?

A. Apron conveyor
B. Pneumatic conveyor
C. Bucket elevator
D. Both B. & C.
Answer» E.
43.

Velocity of a small particle of diameter ‘Dp’ at a distance ‘r’ from the rotational axis of a cyclone rotating at an angular speed ‘ω’ is given by (the other symbols are as per standard notation) ?

A. [(DP/18). (ρs – ρ/μ)] ω2r
B. [(DP2/18). (ρs – ρ/μ)] ω2r
C. [(DP/18). (ρs – ρ/μ)] ω2r2
D. [(DP2/18). (ρs – ρ/μ)] ω2r
Answer» E.
44.

Vacuum is applied in _______________ zone, in case of a general type continuous rotary drum vacuum filter?

A. Filtering
B. Washing
C. Drying
D. All A., B. & C.
Answer» E.
45.

Vacuum filter is most suitable for the_______________?

A. Removal of fines from liquid
B. Liquids having high vapour pressure
C. Liquids of very high viscosity
D. None of these
Answer» E.
46.

Use of grinding aids results in the ___________________?

A. Enhanced production rate
B. Finer products
C. Both A. & B.
D. Neither A. nor B.
Answer» E.
47.

Use of ‘grinding aids’ is done in _______________ grinding?

A. Dry
B. Wet
C. Ultrafine
D. Intermediate
Answer» B. Wet
48.

Use of baffles in agitators help in minimising the ______________ tendency?

A. Swirling
B. Vortexing
C. Both A. & B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
49.

Ultracentrifuges running at speeds upto 100000 rpm is normally used for the_____________________?

A. Separation of isotopes based on their density or molecular weights difference
B. Concentration of rubber latex
C. Separation of cream from milk
D. Dewaxing of lubricating oil
Answer» B. Concentration of rubber latex
50.

Ultrafine grinders operate principally by_________________?

A. Slow compression
B. Impact
C. Attrition
D. Cutting action
Answer» D. Cutting action