Mass Transfer MCQs

Question 1

To remove all the moisture from a wet solid it requires exposure to __________ air.

Accepted Answer

Perfectly dry

Answer

Highly humid

Answer

High temperature

Answer

None of these

Question 2

Which of the following liquid-vapor contacting devices provides maximum contact surface area for a particular duty?

Accepted Answer

Wetted wall column

Answer

Sieve plate column

Answer

Bubble cap column

Answer

Randomly packed column

Question 3

Components, having widely different boiling point in a binary mixture, can be separated using __________ distillation.

Accepted Answer

Simple

Answer

Molecular

Answer

Extractive

Answer

Steam

Question 4

When the psychometric ratio is __________ then the adiabatic saturation temperature and wet bulb temperature becomes equal.

Accepted Answer

1

Answer

< 1

Answer

> 1

Answer

$$\infty $$

Question 5

Which is the controlling factor for a drum drier?

Accepted Answer

Heat transfer

Answer

Diffusion

Answer

Both A & B

Answer

Neither A nor B

Question 6

Sand is dried in foundaries in a___drier.

Accepted Answer

Fluidisedbed

Answer

Rotary

Answer

Vacuum

Answer

Spray

Question 7

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

Accepted Answer

At < 100

Answer

At > 210.6

Answer

Between 100 and 210

Answer

None of these

Question 8

For turbulent mass transfer in pipes, the Sherwood number depends on the Reynolds number as

Accepted Answer

Re 0.83

Answer

Re 0.33

Answer

Re 0.53

Answer

Re

Question 9

The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives

Accepted Answer

Low pressure drop and low hold up

Answer

Low pressure drop and high hold up

Answer

High pressure drop and low hold up

Answer

High pressure drop and high hold up