Category: Mass Transfer

A. 1000
B. 1500
C. 2000
D. 2500

A. Co-current absorbers are usually used, when the gas to be dissolved in the liquid is a pure
substance
B. In case of gas absorption, HETP is equal to HTU, when both the operating line & the
equilibrium lines are parallel
C. Hatta number is important in case of gas absorption with chemical reaction
D. In actual practice, absorption is an endothermic process, while stripping is an exothermic
process

A. In case of induced draft cooling tower, the fan is placed at the top of the tower
B. Effectiveness of forced draft cooling tower is reduced by the recirculation of the humid and
hot discharged air
C. A natural draft cooling tower is recommended to be used, when the air humidity is low and air
temperature is also low
D. Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb
temperature

A. The binary diffusivity in liquids is of the order of 10-5 cm2/sec
B. Molecular diffusion in solid is much faster than that in liquids
C. Particles movement from higher concentration to lower concentration takes place in diffusion
process
D. According to Poiseuille’s law, the permeability decreases with increase in temperature for
flow of a gas through a given capillary

A. Interfacial surface between liquid and gas phase should be large
B. Time of contact between the two phases should be less
C. Gas velocity should be very low
D. Liquid entrainment should be severe

A. Flow rate of inlet air
B. Relative humidity of outlet air
C. Humidity of inlet air
D. Temperature of the solid

A. 1
B. 2
C. 3
D. 4

A. Penetration
B. Surface renewal
C. Film
D. None of these

A. Higher contact area
B. Better contact of the phase
C. Repeated coalescence & redispersion of the drop phase
D. None of these

A. The mole fraction of solute is directly proportional to the molality of a ‘dilute’ solution
B. For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both
components is nonlinear in the case of steady state unimolal unidirectional diffusion
C. Azeotropes obey Raoult’s law at all temperature
D. The relative volatility of a binary mixture at the Azeotropic composition is 1