Mass Transfer

Question: As the reflux ratio increases, the slope of the operating line for rectifying section
[A].

increases

[B].

decreases

[C].

remains constant

[D].

data insufficient, cannot be predicted

Answer: Option A

Explanation:

No answer description available for this question.

Question: According to the film theory of mass transfer, the mass transfer co-efficient is proportional to (where, D = molecular diffusivity)
[A].

D

[B].

D2

[C].

D0.5

[D].

1/D

Answer: Option A

Explanation:

No answer description available for this question.

Question: In distillation columns, the number of bubble caps per tray primarily depends upon the
[A].

allowable liquid velocity.

[B].

allowable gas velocity.

[C].

allowable gas and liquid velocities.

[D].

feed composition.

Answer: Option C

Explanation:

No answer description available for this question.

Question: For turbulent mass transfer in pipes, the Sherwood number depends on the Reynolds number as
[A].

Re0.33

[B].

Re0.53

[C].

Re0.83

[D].

Re

Answer: Option C

Explanation:

No answer description available for this question.

Question: Molecular diffusivity of a liquid
[A].

increases with temperature.

[B].

decreases with temperature.

[C].

may increase or decrease with temperature.

[D].

is independent of temperature.

Answer: Option A

Explanation:

No answer description available for this question.

Question: For stripping of a gas in a counter current stripper, the operating line
[A].

lies above the equilibrium curve.

[B].

lies below the equilibrium curve.

[C].

can lie above or below the equilibrium curve.

[D].

is always parallel to the equilibrium curve.

Answer: Option C

Explanation:

No answer description available for this question.

Question: In distillation where q is defined as the moles of liquid flow in the stripping section per mole of feed introduced, for saturated liquid feed
[A].

q > 1

[B].

q < 1

[C].

q = 1

[D].

q = 0

Answer: Option C

Explanation:

No answer description available for this question.

Question: For absorbing a sparingly soluble gas in a liquid
[A].

gas side mass transfer co-efficient should be increased.

[B].

liquid side mass transfer co-efficient should be increased.

[C].

liquid side mass transfer co-efficient should be decreased.

[D].

mass transfer co-efficient must be kept constant.

Answer: Option B

Explanation:

No answer description available for this question.

Question: In gas-liquid contact operation, the number of ideal stages, . This is true when the stripping factor ‘S’ is
[A].

S > 1

[B].

S < 1

[C].

S = 1

[D].

S = ∞

Answer: Option A

Explanation:

No answer description available for this question.

Question: Mass transfer co-efficient ‘K’ according to penetration theory varies with mass dif-fusivity as
[A].

D0.5

[B].

D

[C].

1/D

[D].

D1.5

Answer: Option A

Explanation:

No answer description available for this question.