chemical engineering MCQs – Page 200

Practise multiple-choice questions from chemical engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

chemical engineering Mcqs
3981. Which of the following efficiencies can be greater than 100% ?
comments icon0
A. Murphree plate efficiency

B. Overall plate efficiency

C. None of these

D. Point efficiency

3982. The ratio of the total emissive power to the absorptivity for all bodies is same at ther-mal equilibrium. This is ______________ law?
comments icon0

A. Plancks

B. Kirchoffs

C. Stefan-Boltzmann

D. Wiens displacement

3983. _____________ heat exchanger is used for chilling oil to be dewaxed?
comments icon0

A. U-tube

B. Floating head

C. Fixed tube

D. Double pipe
3984. A minimum clearance of about _______________ mm is maintained between the distillation column wall and the bubble cap?
comments icon0

A. 67

B. 38

C. 95

D. 19

3985. Bubble cap plate column is___________________?
comments icon0

A. A differential stage contactor

B. A finite stage contactor

C. A continuous contactor

D. Used only for distillation, not for absorption

3986. Maximum acceptable total liquid gradient over a tray is about _______________ mm?
comments icon0

A. 45.5

B. 30.5

C. 5.5

D. 12.5
3987. For what value of Prandtl number, St = f/2 ?
comments icon0

A. > 1

B. < 1

C. 1

D. 1.5

3988. Seamless pipe is made________________?
comments icon0

A. From rolled strips formed into cylinders and seam-welded

B. By extrusion & casting into static and centrifugal molds

C. By forging a solid round, piercing it by simultaneously rotating & forcing it over a piercer

D. nt and further reducing it by rolling gas drawing

E. Both B. and C.
3989. Reason for operating an evaporator in multiple effects is to secure ___________________?
comments icon0

A. Increased steam economy

B. Decreased steam consumption

C. Both A. and B.

D. Increased capacity

3990. Diameter of the sieve tray column is determined by the_________________?
comments icon0

A. Height of the plate spacing

B. Upper limit of the vapour velocity

C. Lower limit of vapour velocity

D. Hole diameter of the sieve tray

3991. The characteristic dimensionless groups for heat transfer to a fluid flowing through a pipe in laminar flow are_______________?
comments icon0

A. Nu, Pr

B. Re.Gz

C. Nu, Gz

D. Nu, Pr, Re

3992. Multiple effect evaporation accounts for___________________?
comments icon0

A. Lower operating costs

B. Steam economy

C. None of these

D. Investment economy

3993. One kilogram of water at 0C is changed to superheated steam of one atm pressure and 300 C. The major heat consumption in the process will be to________________?
comments icon0
A. Evaporate the water

B. Heat the water from 0C to 100C

C. Data insufficient, cant be predicted

D. To superheat the steam

3994. When warm and cold liquids are mixed, the heat transfer is mainly by_______________?
comments icon0

A. Conduction

B. Convection

C. Radiation

D. Both A. & C.

3995. In a co-current double pipe heat exchanger used for condensing saturated steam over the inner tube, if the entrance and exit conditions of the coolant are interchanged, then the rate of condensation will___________________?
comments icon0

A. Decrease

B. Remain unchanged

C. Either increase or decrease; depends on the coolant flow rate

D. Increase

3996. For heat flow through very thick walled cylinder, use ___________mean radius?
comments icon0

A. Either A. or C.

B. Geometric

C. Logarithmic

D. Arithmetic

3997. Steam trap is used to_________________?
comments icon0
A. Remove water resulting from partial condensation of steam

B. None of these

C. Stop the supply of steam

D. Condense the steam flowing in the pipeline

3998. For annular flow of a fluid, the ratio of the equivalent diameter for pressure drop calculation to the equivalent diameter for heat transfer calculation is_________________?
comments icon0

A. (d1 + d2)/d2

B. d2/(d1 + d2)

C. (d1 + d2)/d1

D. d1/(d1 + d2)
3999. In a shell and tube heat exchanger, triangular pitch arrangement as compared to square pitch arrangement ?
comments icon0

A. efficient

B. e fluid

C. Results in higher shell side pressure drop

D. Creates relatively lower turbulence on the shell side resulting in lower shell side heat transfer

E. Can accomodate less number of tubes for a given shell diameter

F. Facilitates easier shell side cleaning; hence is more suitable for handling high dirt factor shell

4000. Which of the following has maximum thermal conductivity ?
comments icon0

A. Nitrogen

B. Tar

C. Coal

D. Iron