Question 1

Which of the following is the most suitable for extraction in a system having very low density difference?

Accepted Answer

Centrifugal extractor

Question 2

Low viscosity absorbent is preferred for reasons of

Accepted Answer

all (a), (b) and (c).

Question 3

Raoult's law applies to the

Accepted Answer

solvents.

Question 4

Which of the following quantities need not be fixed before starting the design of a co-current absorber?

Accepted Answer

Flow rate of entering liquid

Question 5

Psychrometry deals with the properties of gas-vapor mixture. Humidity can be determined by the measurement of the __________ of a fibre.

Accepted Answer

electrical resistance

Question 6

Absorption accompanied with chemical reaction is exemplified by the absorption of

Accepted Answer

SO2 in alkaline solution.

Question 7

Physical absorption is

Accepted Answer

both (b) and (c)

Question 8

In a packed absorption tower, if the equilibrium and operating lines are both straight lines, then the ratio, HETP/HTUOG __________ the absorption factor.

Accepted Answer

both (a) and (b)

Question 9

Make up water is required in a cooling tower to replace the water lost by

Accepted Answer

all (a), (b) and (c)

Question 10

Pick out the correct statement.

Accepted Answer

all (a), (b) and (c).

Question 11

Mass transfer co-efficient (K) and diffusivity (D) are related according to film theory as

Accepted Answer

K ∝ D

Question 12

Fenske equation determines the

Accepted Answer

minimum number of theoretical plates.

Question 13

Stefan's law describes the mass transfer by

Accepted Answer

both 'a' & 'b'

Question 14

At minimum reflux ratio for a given separation

Accepted Answer

number of plates is infinity.

Question 15

Relative humidity is the ratio of the

Accepted Answer

partial pressure of the vapour to the vapour pressure of the liquid at gas temperature.

Question 16

Separation of two or more components of a liquid solution can not be achieved by

Accepted Answer

absorption

Question 17

Which of the following liquid-vapor contacting devices provides maximum contact surface area for a particular duty?

Accepted Answer

Wetted wall column

Question 18

In a solution containing 0.30 Kg mole of solute and 600 kg of solvent, the molality is

Accepted Answer

0.50

Question 19

The amount of steam required per unit quantity of distillate in case of steam distillation will be reduced by

Accepted Answer

both (a) and (b).

Question 20

Chemisorption (chemical adsorption) is

Accepted Answer

an irreversible phenomenon.

Mass Transfer Questions