Mass Transfer MCQs

Question 1

The rate of solid-liquid extraction is limited by the

Accepted Answer

All of the above

Answer

Phase change of the solute as it dissolves in the solvent

Answer

Diffusion of the solute through the solvent in the pores to the outside of the particle

Answer

Diffusion of the solute from the solution in contact with the particle to the main bulk of the solution

Question 2

The McCabe Δ L law states that the

Accepted Answer

Linear crystal growth rate does not depend on the crystal size

Answer

Molar heats of vaporisation of components are nearly equal

Answer

Linear crystal growth rate depends on the degree of supersaturation

Answer

Linear crystal growth rate depends on the crystal size

Question 3

In distillation, overhead product contains

Accepted Answer

Any number of components

Answer

Only one component

Answer

Two components

Answer

Only saturated liquid

Question 4

Which of these columns incurs the lowest pressure drop?

Accepted Answer

Packed column (with stacked packing)

Answer

Packed column (with dumped packing)

Answer

Bubble plate column

Answer

Pulse column

Question 5

At 750°K and 1 atm, the approximate value of Schmidt number for air is

Accepted Answer

0.1

Answer

0.01

Answer

1

Answer

10

Question 6

The commonly used solvent in supercritical extraction is

Accepted Answer

Carbon dioxide

Answer

Methyl ethyl ketone

Answer

Water

Answer

Carbon tetrachloride

Question 7

Pick out the correct statement.

Accepted Answer

All of the above

Answer

In case of liquid-liquid extraction, no separation is possible, if the selectivity of the solvent used is unity

Answer

With increase in temperature, the selectivity of the solvent used in solvent extraction decreases

Answer

The selectivity of solvent used in solvent extraction is unity at the plait point

Question 8

Large scale drying of sugar is done in a __________ dryer.

Accepted Answer

Rotary

Answer

Spouted bed

Answer

Tray

Answer

Truck

Question 9

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

Accepted Answer

+ve

Answer

-ve

Answer

Zero

Answer

None of these