Explore topic-wise MCQs in Chemical Engineering.

This section includes 590 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

301.

Inside the distillation column, the________________________?

A. Driving force for the vapour flow is the pressure drop
B. Liquids are not always at their bubble points
C. Pressure increases gradually from bottom to the top of the column
D. None of these
Answer» B. Liquids are not always at their bubble points
302.

Inside the distillation columns, the ________________________?

A. Highest temperatures is near the feed plate
B. Driving force for the liquid flow is its weight
C. Vapors are not always at their dew points
D. All A., B. and C.
Answer» C. Vapors are not always at their dew points
303.

In triangular co-ordinates, the ternary composition point falls ___________________ of the triangle?

A. In the corners
B. Inside
C. On the sides
D. None of these
Answer» C. On the sides
304.

In the layout plan for a vacuum distillation unit, operating at 60 mm Hg, supported by a barometric condenser, the appropriate place for the location of vacuum drum for collecting the distillate will be_____________________?

A. At ground level
B. 2 metres above the ground
C. 5 metres above ground
D. 10 metres above ground
Answer» B. 2 metres above the ground
305.

In the layout plan for a vacuum distillation unit, operating at 60 mm Hg, supported by a barometric condenser, the appropriate place for the location of vacuum drum for collecting the distillate will be___________________?

A. At ground level
B. 2 metres above the ground
C. 5 metres above ground
D. 10 metres above ground
Answer» B. 2 metres above the ground
306.

In the desorption of highly soluble gas from the liquid, the main resistance will be in the ______________ phase?

A. Gas
B. Liquid
C. Both A. & B.
D. Neither A. nor B.
Answer» C. Both A. & B.
307.

In the constant rate period of the rate of drying curve for batch drying,_________________?

A. Cracks develop on the surface of the solid
B. Rate of drying decreases abruptly
C. Surface evaporation of unbound moisture occurs
D. None of these
Answer» D. None of these
308.

In the absorption of ammonia in water, the main resistance to absorption is by the _________________ phase?

A. Liquid
B. Gas
C. Both A. & B.
D. Neither A. nor B.
Answer» C. Both A. & B.
309.

In stripping section of continuous distillation column, the_______________________?

A. Liquid is stripped of high boiler
B. Liquid is enriched with high boiler
C. Vapour is stripped of low boiler
D. None of these
Answer» C. Vapour is stripped of low boiler
310.

In steam distillation, the _____________________?

A. Temperature is 100°C
B. Temperature is more than 100° C
C. Product must be immiscible with water
D. Temperature is higher than the boiling point of either component
Answer» D. Temperature is higher than the boiling point of either component
311.

In saturated gas, the__________________?

A. Vapour is in equilibrium with the liquid at the gas temperature
B. Vapour is in equilibrium with the liquid at the room temperature
C. Partial pressure of vapour equals the vapour pressure of the liquid at room temperature
D. None of these
Answer» B. Vapour is in equilibrium with the liquid at the room temperature
312.

In rectifying section of a continuous distillation column, the____________________?

A. Vapour is enriched with low boilers
B. Vapour is enriched with high boilers
C. Liquid is stripped of high boilers
D. None of these
Answer» C. Liquid is stripped of high boilers
313.

In physical terms, Schmidt number means _________________?

A. Thermal diffusivity/mass diffusivity
B. Thermal diffusivity/momentum diffusivity
C. Momentum diffusivity/mass diffusivity
D. Mass diffusivity/thermal diffusivity
Answer» D. Mass diffusivity/thermal diffusivity
314.

In paper industry, paper is dried in a _____________ dryer ?

A. Tunnel
B. Heated cylinder
C. Conveyor
D. Festoon
Answer» C. Conveyor
315.

In most of the vacuum crystalliser, vacuum is generally produced by means of a_____________________?

A. Suction pump
B. Compressed air jet
C. Steam jet ejector with a barometric condenser
D. None of these
Answer» D. None of these
316.

In most of the mechanically agitated liquid-liquid extractors, baffles or horizontal compartmental plates are provided, which helps in_________________?

A. Reducing the axial mixing
B. Increasing the rate of extraction
C. Maintaining the concentration difference between the two phases
D. All A , B & C.
Answer» E.
317.

In McCabe-Thiele method of theoretical plate calculation for a distillation column, the operating lines of stripping and rectifying sections coincide with the diagonal at ________________ reflux ?

A. Total
B. Minimum
C. Operating
D. Maximum permissible
Answer» B. Minimum
318.

In McCabe-Thiele method, at infinite reflux ratio________________?

A. The overhead product is minimum
B. Both the operating lines coincide with diagonal
C. Both A. and B.
D. Neither A. nor B.
Answer» B. Both the operating lines coincide with diagonal
319.

In McCabe-Thiele method, at infinite reflux ratio___________________?

A. Number of plates is maximum
B. Overhead product is maximum
C. Both the operating lines coincide with the diagram
D. None of these
Answer» D. None of these
320.

In liquid-liquid extraction, the number of phases at plait point is __________________?

A. 1
B. 2
C. 3
D. 4
Answer» B. 2
321.

In liquid extraction, if the selectivity is unity, then___________________?

A. Separation of the constituents is the most effective
B. No separation will occur
C. Amount of solvent required will be minimum
D. Solvent flow rate should be very low
Answer» C. Amount of solvent required will be minimum
322.

In liquid extraction, if the selectivity is unity, then__________________?

A. Separation of the constituents is the most effective
B. No separation will occur
C. Amount of solvent required will be minimum
D. Solvent flow rate should be very low
Answer» C. Amount of solvent required will be minimum
323.

In gas-liquid contact operation, the number of ideal stages, N = (xa – xb)/(xb – x*b). This is true when the stripping factor ‘S’ is ________________?

A. S > 1
B. S < 1
C. S = 1
D. S = ∞
Answer» B. S < 1
324.

In extraction, as the temperature increases, the area of heterogeneity (area covered by binodal curve)________________?

A. Decreases
B. Increases
C. Remains unchanged
D. None of these
Answer» B. Increases
325.

In extractive distillation, solvent is_____________________?

A. Added to alter the relative volatility of the mixture
B. Of high volatility
C. Present in overhead stream
D. Of high viscosity to give high tray efficiency
Answer» B. Of high volatility
326.

In extraction, as the temperature increases, the area of heterogeneity (area covered by binodal curve)____________________?

A. Decreases
B. Increases
C. Remains unchanged
D. None of these
Answer» B. Increases
327.

In distillation where q is defined as the moles of liquid flow in the stripping section per mole of feed introduced, for saturated liquid feed____________________?

A. q > 1
B. q < 1
C. q = 1
D. q = 0
Answer» D. q = 0
328.

In distillation, overhead product contains ______________________?

A. Only one component
B. Two components
C. Any number of components
D. Only saturated liquid
Answer» D. Only saturated liquid
329.

In distillation columns, the number of bubble caps per tray primarily depends upon the_______________________?

A. Allowable liquid velocity
B. Allowable gas velocity
C. Allowable gas and liquid velocities
D. Feed composition
Answer» D. Feed composition
330.

In continuous distillation, the internal reflux ratio (Ri) and the external reflux ratio (Re) are related as_____________________?

A. Ri = Re/(1 – Re)
B. Ri = (1 – Re)/Re
C. Ri = Re
D. Ri = Re/(1 + Re)
Answer» E.
331.

In case of unsaturated air____________________?

A. Dew point < wet bulb temperature
B. Wet bulb temperature < dry bulb temperature
C. Both A. and B.
D. Neither A. not B.
Answer» D. Neither A. not B.
332.

In case of unsaturated air_________________?

A. Dew point < wet bulb temperature
B. Wet bulb temperature < dry bulb temperature
C. Both A. and B.
D. Neither A. not B.
Answer» D. Neither A. not B.
333.

In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because_______________?

A. Temperature is less
B. Total pressure is less
C. Mixing of steam with the material being vaporised is not so intimate as to result in equilibrium condition
D. Saturated steam is used for steam distillation
Answer» D. Saturated steam is used for steam distillation
334.

In case of physical adsorption, the difference between heat of adsorption and heat of normal condensation is_________________?

A. Equal to the heat of formation of surface compound
B. Equal to the heat of wetting
C. Zero
D. Called integral heat of adsorption
Answer» C. Zero
335.

In case of physical adsorption, the difference between heat of adsorption and heat of normal condensation is__________________?

A. Equal to the heat of formation of surface compound
B. Equal to the heat of wetting
C. Zero
D. Called integral heat of adsorption
Answer» C. Zero
336.

In case of non-ideal gases and liquids, the molal diffusivity ________________?

A. Varies inversely as the pressure
B. Varies directly as the pressure
C. Is independent of pressure
D. Is equal to the volumetric diffusivity
Answer» D. Is equal to the volumetric diffusivity
337.

In case of liquids, the binary diffusivity is proportional to (where, T = temperature) _____________________?

A. T
B. √T
C. T2
D. 1/T
Answer» B. √T
338.

In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the__________________?

A. Temperature and pressure
B. Concentration
C. Nature of the constituents
D. None of these
Answer» E.
339.

In case of gases, the binary diffusivity is proportional to (where, P = pressure) ?

A. P
B. 1/P
C. 1/√P
D. √P
Answer» C. 1/√P
340.

In case of ______________ distillation, a solvent is added to alter the relative volatility of the mixture to be separated?

A. Molecular
B. Azeotropic
C. Extractive
D. Flash
Answer» D. Flash
341.

In case of constant underflow extraction operation, the _______________________ at all solute concentration?

A. Solids are drained to the same extent
B. Ratio of the insoluble to solution is constant
C. Both A. & B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
342.

In case of cooling towers, the ratio of the rates of heat and mass transfer is indicated by the ______________ number ?

A. Lewis
B. Grashoff
C. Sherwood
D. None of these
Answer» B. Grashoff
343.

In case of binary distillation, increasing the reflux ratio above optimum does not result in the increase of_______________________?

A. Area between operating line and 45° diagonal x-y diagram
B. Condenser and reboiler surfaces
C. Tower cross-section
D. None of these
Answer» B. Condenser and reboiler surfaces
344.

In case of an unsaturated mixture of gas and vapor, the percentage saturation is __________________ its relative saturation?

A. Lower than
B. Higher than
C. Equal to
D. Either A. or B., depends on the mixture composition
Answer» B. Higher than
345.

In case of an ideal solution, the total vapor pressure varies ______________ with the composition expressed as mole fraction?

A. Inversely
B. Linearly
C. Exponentially
D. None of these
Answer» C. Exponentially
346.

In case of absorption with exothermic reaction, for fluids having ___________________?

A. Pr = Sc; percentage change in heat and mass transfer flux will be the same for a given change in the degree of turbulence
B. Pr = Sc = 1; total mass, momentum and thermal diffusivity will be the same
C. Both A. and B.
D. Pr = Sc; there won’t be any change in heat and mass transfer flux with changes in degree of turbulence
Answer» D. Pr = Sc; there won’t be any change in heat and mass transfer flux with changes in degree of turbulence
347.

In case of an absorber, the operating _______________?

A. Line always lies above the equilibrium curve
B. Line always lies below the equilibrium curve
C. Line can be either above or below the equilibrium curve
D. Velocity is more than the loading velocity
Answer» B. Line always lies below the equilibrium curve
348.

In case of absorption & stripping, the interface of the liquid & gas phases are present in equilibrium, when the diffusional resistance of _______________ is zero?

A. Interface
B. Gas phase
C. Liquid phase
D. All A , B. & C.
Answer» B. Gas phase
349.

In case of absorption, both the operating and equilibrium lines will be straight for______________?

A. Isothermal operation
B. Dilute solutions
C. Dilute solutions and isothermal operation
D. None of these
Answer» D. None of these
350.

In case of a desorber (stripper), the________________?

A. Operating line always lies above the equilibrium curve
B. Operating line always lies below the equilibrium curve
C. Temperature remains unaffected
D. Temperature always increases
Answer» C. Temperature remains unaffected