Mass Transfer MCQs

Question 1

Azeotropic distillation is employed to separate

Accepted Answer

Constant boiling mixture

Answer

High boiling mixture

Answer

Mixture with very high relative volatility

Answer

Heat sensitive materials

Question 2

Smoke is an example of

Accepted Answer

Solid dispersed in gas

Answer

Solid dispersed in liquid

Answer

Liquid dispersed in gas

Answer

Gas dispersed in liquid

Question 3

In rectifying section of a continuous distillation column, the

Accepted Answer

Vapour is enriched with high boilers

Answer

Vapour is enriched with low boilers

Answer

Liquid is stripped of high boilers

Answer

None of these

Question 4

In batch distillation with constant reflux, overhead product composition __________ with time.

Accepted Answer

Decreases

Answer

Increases

Answer

Does not vary

Answer

May increase on decrease, depends on the system

Question 5

In case of absorption with exothermic reaction, for fluids having

Accepted Answer

Both A & B

Answer

Pr = Sc; percentage change in heat and mass transfer flux will be the same for a given change in the degree of turbulence

Answer

Pr = Sc = 1; total mass, momentum and thermal diffusivity will be the same

Answer

Pr = Sc ; there won

Question 6

The binary diffusivity in gases and liquids vary respectively as

Accepted Answer

$${{	ext{T}}^{\frac{3}{2}}}$$ and T

Answer

T and $${{	ext{T}}^{\frac{3}{2}}}$$

Answer

$$\sqrt {	ext{T}} $$ and $${{	ext{T}}^{\frac{3}{2}}}$$

Answer

$${{	ext{T}}^{\frac{3}{2}}}$$ and $$\sqrt {	ext{T}} $$

Question 7

For absorbing a sparingly soluble gas in a liquid

Accepted Answer

Liquid side mass transfer co-efficient should be increased

Answer

Gas side mass transfer co-efficient should be increased

Answer

Liquid side mass transfer co-efficient should be decreased

Answer

Mass transfer co-efficient must be kept constant

Question 8

The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature.

Accepted Answer

None of these

Answer

Dew point

Answer

Wet bulb

Answer

Dry bulb

Question 9

The equipment frequently used for adiabatic humidification-cooling operation with recirculating liquid is

Accepted Answer

Spray chamber

Answer

Natural draft cooling tower

Answer

Induced draft cooling tower

Answer

None of these