Mass Transfer MCQs

Question 1

Desirable value of absorption factor in an absorber is

Accepted Answer

> 1

Answer

1

Answer

< 1

Answer

0.5

Question 2

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

Accepted Answer

Liquid

Answer

Gas

Answer

Both A & B

Answer

Neither A nor B

Question 3

In an absorber, HETP does not vary with the

Accepted Answer

None of these

Answer

Flow rate of liquid

Answer

Flow rate of gas

Answer

Type and size of packing

Question 4

Pick out the wrong statement:

Accepted Answer

Fenske-Underwood equation is used for calculating theoretical number of plates in a distillation column at normal operating reflux condition

Answer

Reboiler is not used in open steam distillation

Answer

The separation of solutes of different molecular sizes in a liquid solution by use of a suitable membrane is called dialysis

Answer

Freeze drying is used for the drying of fish

Question 5

Component A is diffusing in a medium B. The flux N A relative to a stationary point is equal to the flux due to molecular difusion, if

Accepted Answer

There is equimolar counter diffusion

Answer

Mass transfer is accompanied by reaction

Answer

Diffusion of A is in stagnant medium B

Answer

Molecular mean free path is high

Question 6

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

Accepted Answer

Dilute solutions and isothermal operation

Answer

Isothermal operation

Answer

Dilute solutions

Answer

None of these

Question 7

__________ is concerned with the adsorption equilibria.

Accepted Answer

Freundlich equation

Answer

Fick's law

Answer

Gibb's equation

Answer

None of these

Question 8

If R m is the minimum reflux ratio, the optimum reflux ratio may be around __________ R m .

Accepted Answer

1.2 to 1.5

Answer

2.5 to 3

Answer

3 to 4

Answer

5

Question 9

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

Accepted Answer

All of the above

Answer

Increasing the air velocity and area of exposed wet surface

Answer

Reducing the barometric pressure

Answer

Reducing the humidity of the air