Explore topic-wise MCQs in Chemical Engineering.

This section includes 591 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.

51.

Use of packed towers for distillation is generally limited to the%!

A. Small sizes
B. Multicomponent distillation
C. High pressure operation
D. Vacuum distillation
Answer» B. Multicomponent distillation
52.

Which of the following is not a continuous leaching equipment?%!

A. Pachuka tank
B. Kennedy extractor
C. Bollman extractor
D. Hydrocyclones
Answer» B. Kennedy extractor
53.

The main reason for dividing a tall packed tower into series of small towers is to%!

A. Minimise the overall pressure drop
B. Avoid flooding
C. Reduce liquid hold up
D. Avoid channeling
Answer» E.
54.

When the liquid over a plate is of uniform concentration, then%!

A. Murphree efficiency > point efficiency
B. Murphree efficiency < point efficiency
C. Murphree efficiency = point efficiency
D. Murphree efficiency ‚Äö√¢‚Ä point efficiency
Answer» D. Murphree efficiency ‚Äö√¢‚Ä point efficiency
55.

Separation of two or more components of a liquid solution can not be achieved by%!

A. Fractional crystallisation
B. Liquid extraction
C. Absorption
D. Evaporation
Answer» D. Evaporation
56.

*$___________ column is used in gas absorption process.?

A. Wetted wall
B. Seive/perforated tray
C. Bubble cap
D. Packed
Answer» E.
57.

*$_Smoke is an example of?

A. Solid dispersed in liquid
B. Solid dispersed in gas
C. Liquid dispersed in gas
D. Gas dispersed in liquid
Answer» C. Liquid dispersed in gas
58.

*$_At what value of reflux ratio, number of theoretical plates in a distillation column is minimum??

A. 0
B. 1
C. ‚Äö√ √ª
D. < 1
Answer» D. < 1
59.

*$_Unsaturated air (with dry bulb temperature and dew point being 35°C and 18°C respectively) is passed through a water spray chamber maintained at 15°C. The air will be cooled?

A. And humidified
B. And dehumidified with increase in wet bulb temperature
C. At the same relative humidity
D. And dehumidified with decrease in wet bulb temperature
Answer» E.
60.

*$___________ extractor uses centrifugal force for separating the two phases.?

A. Treybal
B. Schiebel
C. Podbielniak
D. None of these
Answer» D. None of these
61.

*$_Separation of __________ employs gaseous diffusion process.?

A. N‚ÇÇ and O‚ÇÇ from air
B. Isotopes of uranium
C. Isotopes of helium
D. SO‚ÇÇ and air
Answer» C. Isotopes of helium
62.

*$_Plate efficiency?

A. Is a function of the mass transfer between liquid and vapour
B. Increases due to foaming
C. Increases due to liquid entrainment
D. Increases due to weeping and dumping of liquid
Answer» B. Increases due to foaming
63.

*$_With increase in the mass velocity of the gas, the rate of drying during the constant rate period __________ , if the conduction and radiation through the solid are negligible.?

A. Increases
B. Decreases
C. Remains same
D. Increases linearly
Answer» B. Decreases
64.

*$_In batch distillation with constant reflux, overhead product composition __________ with time.?

A. Increases
B. Decreases
C. Does not vary
D. May increase on decrease, depends on the system
Answer» C. Does not vary
65.

*$_Bound moisture is that liquid which exerts an equilibrium vapor pressure __________ that of the pure liquid at the given temperature.?

A. Less than
B. More than
C. Equal to
D. Either A or B; depends on the solid
Answer» B. More than
66.

*$_Antibiotics are best handled in a?

A. Podbielniak extractor
B. Sieve tray contractor
C. Rotating disc contactor
D. Pulsed column extractor
Answer» B. Sieve tray contractor
67.

*$_If a‚ÇÅ and a‚ÇÇ are the relative volatilities when the pressure in the distillation column is 1 and 2 atm respectively. Pick out the correct statement.?

A. a‚ÇÅ = a‚ÇÇ
B. a‚ÇÅ = 2a‚ÇÇ
C. a‚ÇÅ = 0.5 a‚ÇÇ
D. None of these
Answer» E.
68.

*$_As the reflux ratio decreases, the?

A. Separation becomes more efficient
B. Number of plates increases
C. Column diameter increases
D. None of these
Answer» C. Column diameter increases
69.

*$_In a binary system, separation is very efficient, when the relative volatility is?

A. 1
B. > 1
C. < 1
D. 0.5
Answer» C. < 1
70.

*$_According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B? Assume that relative volatility (αAB = 2) does not change appreciably in the coloumn.?

A. 5
B. 9
C. 12
D. 28
Answer» D. 28
71.

*$_Large scale usage of flash distillation is practised in?

A. Soap manufacturing
B. Ammonia synthesis plant
C. Polymerisation industry
D. Petroleum refinning
Answer» E.
72.

*$_With increase in the concentration of the adsorbate, the integral heat of adsorption?

A. Increases
B. Decreases
C. Remains unchanged
D. May increase or decrease ; depends on the type of adsorbate
Answer» C. Remains unchanged
73.

*$_Separation of the isotopes of helium for scientific investigations is done by?

A. Reverse osmosis
B. Thermal diffusion
C. Leaching
D. Solvent extraction
Answer» C. Leaching
74.

*$_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
75.

*$_Nitrobenzene (boiling point = 210.6°C) is steam distilled at 1 atm pressure.Nitrobenzene will distill off __________ °C.?

A. At < 100
B. At > 210.6
C. Between 100 and 210
D. None of these
Answer» B. At > 210.6
76.

*$_With increase in solvent rate, the number of transfer units, NtoG, for a fixed degree of absorption from a fixed amount of gas?

A. Increases
B. Decreases
C. Decreases linearly
D. Remains unaffected
Answer» C. Decreases linearly
77.

*$_At __________ reflux, theoretical number of plates in a distillation coloumn is calculated using Fenske-Underwood equation.?

A. Operating
B. Total
C. Minimum
D. Maximum permissible
Answer» C. Minimum
78.

*$_Lewis number (Le) is?

A. Sc x Pr
B. Pr x St
C. Sh x Pr
D. St x Sh
Answer» B. Pr x St
79.

*$_With decrease in the throughput (compared with the design capacity) for a bubble cap distillation column, its efficiency?

A. Increases
B. Decreases
C. Remains same
D. May increase or decrease ; depends on individual design
Answer» B. Decreases
80.

*$_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
81.

*$_Large scale drying of sugar is done in a __________ dryer.?

A. Spouted bed
B. Tray
C. Rotary
D. Truck
Answer» D. Truck
82.

*$_Desulphurisation of petrol is done in a?

A. Bollman extractor
B. Rotating disc extractor
C. Packed extraction column
D. Plate type extraction column
Answer» C. Packed extraction column
83.

*$___________ is concerned with the adsorption equilibria.?

A. Fick's law
B. Gibb's equation
C. Freundlich equation
D. None of these
Answer» D. None of these
84.

*$_Dorr thickener is an equipment used for?

A. Classification
B. Sedimentation
C. Clarification
D. Leaching
Answer» C. Clarification
85.

*$_H‚ÇÇS present in naphtha reformed gas is removed by absorbing with?

A. Ethanolamine
B. K‚ÇÇCO‚ÇÉ
C. HCl
D. Vacuum gas oil
Answer» B. K‚Äö√á√áCO‚Äö√á√â
86.

*$_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 of the above
Answer» E.
87.

*$_Separation of a mixture of two gases by absorption in the liquid solvent depends upon the difference in their?

A. Viscosity
B. Density
C. Solubility
D. Relative volatility
Answer» D. Relative volatility
88.

*$_At a fixed pressure, the humidity depends upon the partial pressure of vapor in the mixture. Humidity of a vapour free gas is __________ percent.?

A. 100
B. 0
C. 50
D. Between 0 and 100
Answer» C. 50
89.

*$_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
90.

*$_The value of NA/(NA + NB) for steady state molecular diffusion of gas 'A' through non-diffusing gas 'B' is?

A. 1
B. ‚Äö√ √ª
C. 0.5
D. 2
Answer» B. ‚Äö√ √ª
91.

*$_Heat sensitive materials like certain pharmaceuticals and food stuffs can be dried in a/an __________ dryer.?

A. Indirect tray
B. Spray
C. Freeze
D. None of these
Answer» D. None of these
92.

*$_Which of the following can be calculated theoretically using steam table and Dalton's law of partial pressure; if the relative humidity and dry bulb temperature of moist air is known??

A. Dew point
B. Humidity ratio
C. Wet bulb temperature
D. None of these
Answer» D. None of these
93.

*$_Use of packed towers for distillation is generally limited to the?

A. Small sizes
B. Multicomponent distillation
C. High pressure operation
D. Vacuum distillation
Answer» B. Multicomponent distillation
94.

*$_Which of the following is not a continuous leaching equipment??

A. Pachuka tank
B. Kennedy extractor
C. Bollman extractor
D. Hydrocyclones
Answer» B. Kennedy extractor
95.

*$_When the liquid over a plate is of uniform concentration, then?

A. Murphree efficiency > point efficiency
B. Murphree efficiency < point efficiency
C. Murphree efficiency = point efficiency
D. Murphree efficiency ‚Äö√¢‚Ä point efficiency
Answer» D. Murphree efficiency ‚Äö√¢‚Ä point efficiency
96.

*$_Separation of two or more components of a liquid solution can not be achieved by?

A. Fractional crystallisation
B. Liquid extraction
C. Absorption
D. Evaporation
Answer» D. Evaporation
97.

*$_Low viscosity absorbent is preferred for reasons of?

A. Rapid absorption rates and good heat transfer characteristics
B. Improved flooding characteristics
C. Low pressure drop on pumping
D. All of the above
Answer» E.
98.

*$_The main reason for dividing a tall packed tower into series of small towers is to?

A. Minimise the overall pressure drop
B. Avoid flooding
C. Reduce liquid hold up
D. Avoid channeling
Answer» E.
99.

*$_A minimum boiling azeotrope is exemplified by?

A. Toluene-benzene
B. Acetone-carbon disulphide
C. Water-isobutyl alcohol
D. None of these
Answer» C. Water-isobutyl alcohol
100.

*$_When a multistage tray tower uses a minimum reflux ratio, it implies?

A. Infinite trays and maximum reboiler heat load
B. Infinite trays and minimum reboiler heat load
C. Minimum trays and minimum reboiler heat load
D. Minimum trays and maximum reboiler heat load
Answer» B. Infinite trays and minimum reboiler heat load