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.

151.

The diffusivity, DAB (for component A diffusing in B) is equal to the diffusivity DBA (for component B diffusing in A) for a binary mixture of________________?

A. Newtonian liquids
B. Non-Newtonian liquids
C. Ideal gases
D. Real gases
Answer» D. Real gases
152.

The diffusivity D. in a binary gas mixture is related to the temperature (T) as________________________?

A. D ∝ T
B. D ∝ T0.5
C. D ∝ T1.5
D. D ∝ T2
Answer» D. D ∝ T2
153.

The diffusivity D. in a binary gas mixture is related to the pressure (P) as__________________?

A. D ∝ P0.5
B. D ∝ 1/P0.5
C. D ∝ 1/P
D. D ∝ 1/P1.5
Answer» D. D ∝ 1/P1.5
154.

The diffusivity D. in a binary gas mixture is related to the pressure (P) as___________________?

A. D ∝ P0.5
B. D ∝ 1/P0.5
C. D ∝ 1/P
D. D ∝ 1/P1.5
Answer» D. D ∝ 1/P1.5
155.

The diffusion co-efficient in m2/s. of acetic acid in benzene (liquid in liquid) is___________________?

A. 2.09 × 10-4
B. 2.09 × 10-5
C. 2.09 × 10-9
D. 2.09 × 10-12
Answer» B. 2.09 × 10-5
156.

The difference of wet bulb temperature and adiabatic saturation temperature of unsaturated mixture of any system is___________________?

A. +ve
B. -ve
C. Zero
D. None of these
Answer» B. -ve
157.

The dew point of an unsaturated gas-vapor mixture does not depend upon the ____________________ of the mixture?

A. Composition
B. Temperature
C. Total pressure
D. All A., B. and C.
Answer» C. Total pressure
158.

The dew point of an unsaturated gas-vapor mixture does not depend upon the _________________ of the mixture?

A. Composition
B. Temperature
C. Total pressure
D. All A, B. and C.
Answer» C. Total pressure
159.

The dew point of a saturated gas phase equals the ________________ temperature?

A. Gas
B. Room
C. Wet bulb
D. None of these
Answer» B. Room
160.

The critical moisture content in case of drying indicates the _______________ rate period?

A. Beginning of falling
B. Beginning of constant
C. End of falling
D. None of these
Answer» B. Beginning of constant
161.

The critical moisture content in case of drying indicates the ________________ rate period?

A. Beginning of falling
B. Beginning of constant
C. End of falling
D. None of these
Answer» B. Beginning of constant
162.

The cooling effect in a cooling tower can be speeded up by _______________________?

A. Increasing the air velocity and area of exposed wet surface
B. Reducing the barometric pressure
C. Reducing the humidity of the air
D. All A., B. and C.
Answer» E.
163.

The cooling effect in a cooling tower cannot be increased by_____________________?

A. Increasing the air velocity over the wet surfaces
B. Reducing the humidity of entering air
C. Lowering the barometric pressure
D. None of these
Answer» E.
164.

The commonly used solvent in supercritical extraction is_____________________?

A. Methyl ethyl ketone
B. Water
C. Carbon tetrachloride
D. Carbon dioxide
Answer» E.
165.

The change in enthalpy per unit weight of adsorbed gas when adsorbed on gas free or “outgassed” adsorbent to from a definite concentration of adsorbate is called its_____________________?

A. Integral heat of adsorption
B. Heat of wetting
C. Differential heat of adsorption
D. Heat of normal condensation
Answer» B. Heat of wetting
166.

The change in enthalpy, when a unit quantity of gas is absorbed by relatively large quantity of adsorbent (on which a definite concentration of the adsorbed gas already exists) is termed as the_________________?

A. Differential heat of adsorption
B. Heat of wetting
C. Integral heat of adsorption
D. None of these
Answer» B. Heat of wetting
167.

The caking of crystals can be prevented by _____________________?

A. Maintaining high critical humidity
B. Maintaining low critical humidity
C. Coating the product with inert material
D. Both A. and C.
Answer» E.
168.

The boiling points of pure components of a binary system ________________ with increase in total pressure of the system ?

A. Decreases
B. Increases
C. Remains unchanged
D. May increase or decrease, depends on the system
Answer» C. Remains unchanged
169.

The binary diffusivity in gases does not depend upon the ___________________?

A. Pressure
B. Temperature
C. Nature of the components
D. None of these
Answer» E.
170.

The binary diffusivity in gases at atmospheric conditions is about ___________________?

A. 10-9 cm/sec
B. 10-1 cm2/sec
C. 10-3 sec/cm
D. 10-4 cm2/sec2
Answer» C. 10-3 sec/cm
171.

The binary diffusivity in gases and liquids vary respectively as_________________?

A. T3/2 and T
B. T and T3/2
C. √T and T3/2
D. T3/2 and √T
Answer» B. T and T3/2
172.

The assumption made in Elis method in distillation is that enthalpy concentration lines of vapor and liquid are __________________?

A. Parallel
B. Straight
C. Both parallel and straight
D. Neither parallel nor straight
Answer» D. Neither parallel nor straight
173.

The apex of an equilateral-triangular coordinate (in ternary liquid system) represents a/an ___________________?

A. Pure component
B. Binary mixture
C. Ternary mixture
D. Insoluble binary system
Answer» B. Binary mixture
174.

The amount of steam required per unit quantity of distillate in case of steam distillation will be reduced by __________________?

A. Raising the temperature
B. Lowering the total pressure
C. Both A. and B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
175.

The adiabatic saturation curve for a vapour-gas mixture is__________________?

A. Straight line
B. Slightly concave upward
C. Slightly concave downward
D. None of these
Answer» C. Slightly concave downward
176.

The absorption factor is defined as (where, L = liquid flow rate, G = gas flow rate and, m = slope of the equilibrium line) ?

A. L/mG
B. G/mL
C. mL/G
D. LG/m
Answer» B. G/mL
177.

Schmidt number is given by ___________________?

A. μ/ρDAB
B. Re × Pe
C. Sh × Pe
D. Re/Pe
Answer» B. Re × Pe
178.

Schmidt number and Lewis number for pure air at atmospheric conditions are respectively__________________?

A. < 1 and ≈ 1
B. 1 and 0
C. > 1 and ≈ 1
D. 0 and ≈ 1
Answer» B. 1 and 0
179.

Sand is dried in foundries in a ______________________drier?

A. Rotary
B. Fluidised bed
C. Vacuum
D. Spray
Answer» C. Vacuum
180.

Rotary dryers cannot handle _______________ materials ?

A. Free flowing
B. Dry
C. Sticky
D. Granular
Answer» D. Granular
181.

Rose oil is extracted from rose leaves using ____________ distillation?

A. High pressure
B. Low pressure
C. Extractive
D. Steam
Answer» E.
182.

Reverse osmosis is also called_________________?

A. Dialysis
B. Electrodialysis
C. Diffusion
D. Ultra-filtration
Answer» E.
183.

Removal of ______________ exemplifies an adsorption unit operation?

A. Uranium from its ore
B. Water from petrol
C. Ammonia from coke oven gas
D. Mustard oil from mustard seed
Answer» C. Ammonia from coke oven gas
184.

Relative volatility varies with the concentration of component for an ideal solution. The relative volatility of a binary mixture may be defined as the ratio of vapor pressure of component ‘A’ to that of component ‘B’, when_________________?

A. Only vapor phase follows Raoult’s law
B. Only liquid phase obeys Dalton’s law
C. Liquid phase obeys Dalton’s law and vapor phase obeys Raoult’s law
D. Vapor phase obeys Dalton’s law and liquid phase obeys Raoult’s law
Answer» E.
185.

Relative volatility does not change appreciably with the change in_____________________?

A. Temperature
B. Vapour pressure of either component
C. Total pressure
D. None of these
Answer» B. Vapour pressure of either component
186.

Relative humidity is the ratio of the______________________?

A. Partial pressure of the vapour to the vapour pressure of the liquid at room temperature
B. Partial pressure of the vapour to the vapour pressure of the liquid at gas temperature
C. Actual humidity to saturation humidity
D. None of these
Answer» C. Actual humidity to saturation humidity
187.

Refractory bricks are usually dried in a ________________ dryer?

A. Tray
B. Tunnel
C. Conveyor
D. Festoon
Answer» C. Conveyor
188.

Reboiler is considered as one theoretical plate, because_____________________?

A. Of the assumption that vapour and liquid leaving the reboiler are in equilibrium
B. Vapour is recycled to the column
C. Reboiler itself contains one plate
D. None of these
Answer» B. Vapour is recycled to the column
189.

Rayleigh equation applies to _________________ distillation ?

A. Differential
B. Flash
C. Equilibrium
D. Molecular
Answer» B. Flash
190.

Rayleigh’s equation applies to _________________ distillation?

A. Continuous
B. Steam
C. Differential
D. Flash
Answer» D. Flash
191.

Rayleigh’s equation applies to ________________ distillation?

A. Continuous
B. Steam
C. Differential
D. Flash
Answer» D. Flash
192.

Rate of leaching increases with increasing______________________?

A. Temperature
B. Viscosity of solvent
C. Pressure
D. Size of the solid
Answer» B. Viscosity of solvent
193.

Raschig ring made of porcelain cannot be used for treating concentrated___________________?

A. Hydrochloric acid
B. Nitric acid
C. Alkalis
D. Sulphuric acid
Answer» D. Sulphuric acid
194.

Raoult’s law is applicable to the_____________________?

A. Ideal solutions
B. Real solutions
C. Mixture of water and alcohol
D. Non-ideal gases
Answer» B. Real solutions
195.

Raoult’s law does not apply, when the___________________?

A. Size of component molecules are not equal
B. Attractive forces between like and unlike molecules in the solution are approximately equal
C. Component molecules are non-polar
D. Chemical combination or molecular association between unlike molecules takes place in the formation of solution
Answer» D. Chemical combination or molecular association between unlike molecules takes place in the formation of solution
196.

Raoult’s law applies to the___________________?

A. All liquid solutions
B. Non-ideal solution only
C. Non-volatile solute
D. Solvents
Answer» E.
197.

Radioactive nuclear waste is treated in____________________?

A. Mixer-settler extractor
B. Rotating-disc contactor
C. Pulsed column extractor
D. Bollman extractor
Answer» D. Bollman extractor
198.

Psychrometry deals with the properties of gas-vapor mixture. Humidity can be determined by the measurement of the ________________ of a fibre ?

A. Electrical resistance
B. Thermal conductivity
C. Strength
D. None of these
Answer» B. Thermal conductivity
199.

Priming in a distillation column_________________?

A. Results from very low gas velocity
B. Is desirable from point efficiency consideration
C. Is characterised by the presence of foam throughout the space between trays
D. Reduces the overall pressure drop
Answer» D. Reduces the overall pressure drop
200.

Pressure drop through plate tower as compared to that through packed tower, for the same duty will be___________________?

A. Less
B. More
C. Equal
D. Either A. or B.; depends on the packing height
Answer» C. Equal