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Competitive Chemical Engineering MCQs – New Mechanical Operations MCQs

Competitive Chemical Engineering MCQs – New Mechanical Operations MCQs

This post is comprising of latest ” Mechanical Operations MCQs – Latest Competitive Chemical Engineering MCQs “. Here you’ll get latest chemical engineering mcqs for written test, interview with answers. If you want to improve your knowledge regarding chemical engineering then read these mcqs of Design of Steel Structures.

Latest Chemical Engineering MCQs

By practicing these MCQs of Mechanical Operations MCQs – Latest Competitive Chemical Engineering MCQs , an individual for exams performs better than before. This post comprising of mechanical engineering objective questions and answers related to Mechanical Operations Mcqs “. As wise people believe “Perfect Practice make a Man Perfect”. It is therefore practice these mcqs of Chemical engineering to approach the success. Tab this page to check “Mechanical Operations Mcqs” for the preparation of competitive mcqs, FPSC mcqs, PPSC mcqs, SPSC mcqs, KPPSC mcqs, AJKPSC mcqs, BPSC mcqs, NTS mcqs, PTS mcqs, OTS mcqs, Atomic Energy mcqs, Pak Army mcqs, Pak Navy mcqs, CTS mcqs, ETEA mcqs and others.

Latest Mechanical Operations Mcqs

The most occurred mcqs of Mechanical Operations in past papers. Past papers of Mechanical Operations Mcqs. Past papers of Mechanical Operations Mcqs . Mcqs are the necessary part of any competitive / job related exams. The Mcqs having specific numbers in any written test. It is therefore everyone have to learn / remember the related Mechanical Operations Mcqs. The Important series of Mechanical Operations Mcqs are given below:

Size reduction of fibrous materials like wood, asbestos, mica etc. is done by a disintegrator exemplified by the _________________?

A. Stamp mill
B. Cage mill
C. Blake jaw crusher
D. Bradford’s breaker

Specific surface area is the surface area of a unit _______________ of materials?

A. Volume
B. Weight
C. Either A. or B.
D. Neither A. nor B.

Separation of a suspension or slurry into a supernatant clear liquid (free from particles) and a thick sludge containing a high concentration of solid is called__________________?

A. Clarification
B. Sedimentation
C. Classification
D. Decantation

If a force greater than that of gravity is used to separate solids & fluids of different densities, the process is termed as the __________________?

A. Flocculation
B. Sedimentation
C. Dispersion
D. Centrifugation

The ratio of the actual mesh dimension of Taylor series to that of the next smaller screen is_______________?

A. 1.5
B. √2
C. 2
D. √3

The energy consumed by a ball mill depends on__________________?

A. Its ball load
B. Its speed
C. The density of the material being ground
D. All A., B. and C.

Size reduction of asbestos and mica is done by____________________?

A. Hammer mills
B. Gyratory crushers
C. Rod mills
D. Crushing rolls

In case of a hammer crusher, the final product size depends on the____________________?

A. Rotor speed
B. Feed rate
C. Clearance between hammer & grinding plates
D. All A., B. and C.

Tube mill compared to ball mill_______________________?

A. Is long in comparison with its diameter
B. Produces finer products
C. Uses smaller balls
D. All A., B. & C.

Tabling process used for separating two materials of different densities by passing the dilute pulp over a table/deck, which is inclined from the horizontal surface at an angle of about________________?

A. 5 to 10°
B. 2 to 5°
C. 1 to 2°
D. 10 to 15°

To get ultrafine particles, the equipment used is a _________________?

A. Rod mill
B. Ball mill
C. Hammer crusher
D. Fluid energy mill

Kick’s law assumes that the energy required for size reduction is proportional to the logarithm of the ratio between the initial and the final diameters. The unit of Kick’s constant is_________________?

A. kW. sec/kg
B. kWh/sec. kg
C. kWh/kg
D. kg/sec

Filtration rate through a filter cake is proportional to (where, S = filtering surface R = specific cake resistance μ = viscosity of the filtrate) ?

A. 1/R
B. S
C. 1/μ
D. All A., B. & C.

In continuous filtration (at a constant pressure drop), filtrate flow rate varies inversely as the__________________?

A. Square root of the velocity
B. Filtration time only
C. Square of the viscosity
D. Washing time only

The sphericity of a solid particle of cubical shape is ___________________?

A. π/3
B. (π/6)1/3
C. (π/6)1/2
D. π

Mass Transfer Mcqs

To remove dirt from the flowing fluid, we use a ____________________?

A. Gravity settler
B. Coagulant
C. Strains
D. Clarifier

The most suitable equipment used to devulcanise rubber scrap and to make water dispersion & rubber solution is a __________________?

A. Boundary mixer
B. Sharpies centrifuge
C. Propeller agitator
D. None of these

Which of the following may prove unsuitable for filtering volatile liquids ?

A. Gravity filter
B. Pressure filter
C. Centrifugal filter
D. Vacuum filter

A screen is said to be blinded, when the___________________?

A. Screen capacity is abruptly increased
B. Under-sizes are retained in oversize fraction
C. Screen is plugged with solid particles
D. Over-sizes are present in undersize fraction

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

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

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

A. Hanger
B. Toggles
C. Check plates
D. Pitman

Float and sink test determines the possibility of cleaning of coal by a process based on the___________________?

A. Gravity separation
B. Particle shape
C. Wettability
D. None of these

Cumulative analysis for determining surface is more precise than differential analysis, because of the_______________?

A. Fact that screening is more effective
B. Assumption that all particles in a single fraction are equal in size
C. Assumption that all particles in a single fraction are equal in size, is not needed
D. None of these

Sphericity is the ratio of the surface area of a spherical particle having the same volume as the particle to the surface area of the particle. Which of the following has the maximum value of sphericity ?

A. Sphere
B. Raschig rings
C. Cylinder (L/D = 1)
D. Cube

Vacuum filter is most suitable for the_______________?

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

The specific cake resistance for compressible sludges is a function of the pressure drop__________________?

A. Over cake
B. Overall
C. Over medium
D. None of these

In case of grinding in a ball mill__________________?

A. Its capacity decreases with increasing fineness of the products
B. Wet grinding achieves a finer product size than dry grinding
C. Grinding cost and power requirement increases with increasing fineness of the products
D. All A., B. and C

A tube mill as compared to a ball mill__________________?

A. Gives finer size reduction but consumes more power
B. Employs smaller balls
C. Has larger length/diameter ratio (>2 as compared to 1 for ball mill)
D. All A., B. and C.

The unit of filter medium resistance is________________?

A. cm-1
B. cm/gm-1
C. gm/cm-1
D. gm-1

Bucket elevators are not suitable for the vertical lifting of __________ materials?

A. Free flowing
B. Sticky (e.g. clay paste)
C. Small lumpy (e.g. grains and sand)
D. Fine (e.g. – 200 mesh size coal)

A cottrell precipitator makes use of the ______________ for dusty air cleaning?

A. Alternating current
B. Corona discharge
C. Electric spark
D. None of these

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 2α
B. μ ≥ tan α
C. μ > tan α
D. μ ≤ tan α

Fuels And Combustion Mcqs

For raschig rings, the sphericity is_____________________?

A. 1
B. 0.5
C. < 1
D. √3

In washing type plate and frame filter press, the ratio of washing rate to the final filtrate rate is__________________?

A. 1
B. 1/4
C. 4
D. 1/2

Pine oil and Cresylic acid are used as ______________ in the froth floatation process?

A. Frother
B. Depressor
C. Collector
D. Conditioner

Energy requirement (per unit mass of material crushed/ground) is highest for__________________?

A. Rod mill
B. Jaw crusher
C. Ball mill
D. Fluid energy mill

Gold ore concentration is mostly done using___________________?

A. Froth floatation
B. Tabling
C. Jigging
D. Elutriation

Screw conveyors are________________?

A. Suitable for highly abrasive materials
B. Suitable for sticky materials
C. Run at very high rpm
D. All A., B. and C.

A suspension of glass beads in ethylene glycol has a hindered settling velocity of 1.7 mm/s, while the terminal settling velocity of a single glass bead in ethylene glycol is 17 mm/s. If the Richardson-Zaki hindered settling index is 4.5, the volume fraction of solids in the suspension is_____________?

A. 0.4
B. 0.1
C. 0.6
D. None of these

Power consumption during turbulent flow in agitation tank is proportional to the ______________ of the liquid?

A. Thermal conductivity
B. Viscosity
C. Surface tension
D. Density

200 mesh screen means 200 openings per_____________________?

A. cm
B. cm2
C. inch
D. inch2

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

A. Dispersion
B. Comminution
C. Pulverisation
D. Compression

The porosity of a compressible cake is _____________________?

A. Minimum at the filter medium
B. Maximum at the filter medium
C. Minimum at the upstream face
D. Same throughout the thickness of cake

The most common filter aid is_________________?

A. Diatomaceous earth
B. Sodium carbonate
C. Calcium silicate
D. Silica gel

_______________ mill is normally used for grinding of talc?

A. Compartment
B. Tube
C. Ring-roll
D. Pebble

For achieving maximum capacity of the ball mill, the ball charge should be equal to about ______________ percent of the ball mill volume?

A. 25
B. 10
C. 50
D. 75

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

A. Disc-bowl centrifuge
B. Pre-coat filter
C. Sparkler filter
D. Sharpies super-centrifuge

Half the angle of nip, (α), for a roll crusher is given by (where, dr, dp and df are diameters of crushing rolls, feed particles and rolls gap respectively) ?

A. cos α = (dr + dp)/(dr + df)
B. tan α = (dr + dp)/(dr + df)
C. cos α = (dr + df)/(dr + dp)
D. sin α = (dr + dp)/(dr + df)

Mixer used for rubber compounding is__________________?

A. Muller mixer
B. Banbury internal mixer
C. mixer-extruder
D. Pug mill

Froth floatation is the most suitable for treating ____________________?

A. Quartzite
B. Sulphide ores
C. Iron ores
D. None of these

Which of the following must be stored in silos and not in open yard ?

A. Sand
B. High V.M. bituminous coal
C. Coke breeze
D. None of these

Mechanical Operations Mcqs

Sulphuric acid mist is arrested by using a ____________ scrubber?

A. Hollow wet
B. Packed wet
C. Venturi
D. Co-current

Addition of filter aid to the slurry before filtration is done to _______________ of the cake?

A. Increase the porosity
B. Decrease the porosity
C. Increase the compressibility co-efficient
D. Decrease the compressibility co-efficient

Capacity of flight conveyor in tons/hr is given by (where, W & D = width and depth of flight respectively in metre V = speed of the conveyor, metre/second ρ = bulk density of material, kg/m3) ?

A. 3.6 W.D.V.ρ
B. 3.6 W.V.ρ
C. 3.6 W.D.V
D. 3.6 D.V.ρ

For removal of very small amounts of precipitate from large volume of water, the most suitable filter is the ______________ filter?

A. Shell & leaf
B. Plate & frame
C. Sand
D. Rotary vacuum

Which of the following conveyors cannot be recommended for transportation of abrasive materials ?

A. Apron conveyor
B. Belt conveyor
C. Flight conveyor
D. Chain conveyor

Mesh indicates the number of holes per_________________?

A. Square foot
B. Linear inch
C. Square inch
D. Linear foot

Which of the following comes in the category of primary crusher for hard and tough stone ?

A. Jaw crusher
B. Gyratory crusher
C. Cone crusher
D. None of these

Two particles are called to be equal settling, if they are having the same ?

A. Specific gravity
B. Size
C. Terminal velocities in the same fluid & in the same field of force
D. None of these

For a non-spherical particle, the sphericity__________________?

A. Is defined as the ratio of surface area of a sphere having the same volume as the particle to the actual surface area of the particle
B. Has the dimension of length
C. Is the ratio of volume of a sphere having the same surface area as the particle to the actual volume of the particle
D. Is always less than 1

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. [(DP2/18). (ρs – ρ/μ)] ω2r
B. [(DP/18). (ρs – ρ/μ)] ω2r
C. [(DP/18). (ρs – ρ/μ)] ω2r2
D. [(DP2/18). (ρs – ρ/μ)] ω2r

Which of the following is the most suitable for cleaning of fine coal dust (<0.5 mm) ?

A. Baum jig washer
B. Trough washer
C. Spiral separator
D. Froth floatation

Apron conveyors are used for ___________________ ?

A. Heavy loads & short runs
B. Heavy loads & long runs
C. Small loads & long runs
D. None of these

The ratio of the area of openings in one screen (Taylor series) to that of the openings in the next smaller screen is_________________?

A. 1
B. 1.5
C. √2
D. None of these

Which of the following is not a cutting machine ?

A. Knife cutters
B. Dicers
C. Slitters
D. Tube mills

The sphericity of a cylinder of 1 mm diameter and length 3 mm is_________________?

A. 0.9
B. 0.6
C. 0.78
D. 0.5

Separation of materials into products based on the difference of their sizes is called___________________?

A. Sizing
B. Classification
C. Sorting
D. Flocculation

Ultra centrifuges are used for the separation of _____________ solid particles?

A. Fine
B. Coarse
C. Colloidal
D. Dissolved

Sizing of very fine particles of the order of 5 to 10 microns is done by elutriation, which is a _____________ operation?

A. Sedimentation
B. Clarification
C. Flocculation
D. Classification

Run of mine (ROM) coal is crushed by a _________________________ for use in domestic ovens?

A. Ball mill
B. Hammer crusher
C. Jaw crusher
D. Tube mill

Competitive Chemical Engineering MCQs – New Mechanical Operations MCQs