Author name: admin

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.

Question: If the specific heats of a gas and a vapor are 0.2KJ/Kg.°K and 1.5 KJ/Kg.°K respectively, and the humidity is 0.01; the humid heat in KJ/°Kg. is
[A].

0.31

[B].

0.107

[C].

0.017

[D].

0.215

Answer: Option D

Explanation:

No answer description available for this question.

Question: Air initially at 101. 3 kPa and 40°C and with a relative humidity of 50%, is cooled at constant pressure to 30°C. The cooled air has a
[A].

higher dew point.

[B].

higher absolute (specific) humidity.

[C].

higher relative humidity

[D].

higher wet bulb temperature.

Answer: Option C

Explanation:

No answer description available for this question.

Question: In an interphase mass transfer process, the lesser the solubility of a given solute in a liquid, the higher are the chances that the transfer process will be
[A].

liquid phase resistance-controlled.

[B].

gas phase resistance controlled.

[C].

impossible.

[D].

driven by a non-linear driving force.

Answer: Option B

Explanation:

No answer description available for this question.

Question: For a fixed number of ideal stages in a distillation column, as the reflux ratio is increased, the difference in composition between the top and bottom product streams
[A].

increases

[B].

decreases

[C].

remains unaffected

[D].

passes through a maximum

Answer: Option A

Explanation:

No answer description available for this question.

Question: For the air water system under ambient conditions, the adiabatic saturation temperature and the wet bulb temperature are nearly equal, because
[A].

water has a high latent heat of evaporation.

[B].

Lewis number is close to unity.

[C].

they are always equal under all circumstances.

[D].

solubility of the components of air in water is very small.

Answer: Option A

Explanation:

No answer description available for this question.

Question: In distillation column design, the McCabe-Thiele procedure is inadequate and a Ponchan-Savarit procedure is needed, when
[A].

saturated feed is not used.

[B].

an azeotrope forms.

[C].

the latent heat of vaporisation of the more and less volatile components are greatly different.

[D].

a total condenser is used.

Answer: Option D

Explanation:

No answer description available for this question.

Question: Penetration theory states that the mass transfer co-coefficient is equal to (where, De is diffusivity and ‘t’ is time)
[A].

(De.t)1/2

[B].

(De/t)1/2

[C].

(4De/πt)1/2

[D].

(4De/t)

Answer: Option C

Explanation:

No answer description available for this question.

Question: Which of the following provides maximum contact surface for a liquid-vapour system?
[A].

Packed tower

[B].

Bubble-cap plate column

[C].

Seive-plate column

[D].

Wetted wall column

Answer: Option A

Explanation:

No answer description available for this question.