Mass Transfer MCQs

Question 1

For water-ethanol system, the minimum reflux ratio

Accepted Answer

Is computed from the slope of the upper operating line that is tangent to the equilibrium curve

Answer

Is computed from the intercept of the operating line

Answer

Cannot be computed

Answer

Is the optimum reflux ratio

Question 2

In gas-liquid contact operation, the number of ideal stages, $${	ext{N}} = \frac{{{{	ext{x}}_{	ext{a}}} - {{	ext{x}}_{	ext{b}}}}}{{{{	ext{x}}_{	ext{b}}} - {{	ext{x}}^{ * {	ext{b}}}}}}.$$ This is true when the stripping factor 'S' is

Accepted Answer

S > 1

Answer

S < 1

Answer

S = 1

Answer

S = $$\infty $$

Question 3

__________ column is used in gas absorption process.

Accepted Answer

Packed

Answer

Wetted wall

Answer

Seive/perforated tray

Answer

Bubble cap

Question 4

Tray spacing in a distillation column of dia 10-12 ft. used in petroleum refinery may be around __________ inches.

Accepted Answer

30

Answer

5

Answer

60

Answer

100

Question 5

Which of the following remains constant during sensible cooling process ?

Accepted Answer

Both A & B

Answer

Specific humidity

Answer

Partial pressure of vapour

Answer

Neither A nor B

Question 6

For the same process conditions, the reflux ratio of an unlagged distillation column

Accepted Answer

Increases in winter

Answer

Decreases in winter

Answer

Increases in summer

Answer

None of these

Question 7

Which of the following is a suitable absorbent for removal of H 2 S from natural gas?

Accepted Answer

Monoethanol amine (MEA)

Answer

Vetrocoke solution

Answer

Dilute

Answer

Hot water

Question 8

The solvent used in liquid-liquid extraction should have __________ less than one.

Accepted Answer

Neither A nor B

Answer

Selectivity

Answer

Distribution co-efficient

Answer

Both A & B

Question 9

Physical absorption is

Accepted Answer

Both B & C

Answer

An irreversible phenomenon

Answer

A reversible phenomenon

Answer

Accompanied by evolution of heat