A. When the concentration difference for the mass transfer becomes zero at the bottom of the gas
absorption tower, then the upper end of the operating line touches the equilibrium curve
B. The average distance between the operating line and equilibrium line is large, when the liquidgas
ratio is also large in case of a counter current gas absorption tower
C. The operating line lies above the equilibrium curve in case of a gas desorber
D. With decrease in the liquid flow rate for a fixed gas flow rate, the slope of the operating line
decreases, in case of gas absorption process
Related Mcqs:
- Pick out the wrong statement ?
A. Mechanical agitation is required, if the system has low interfacial tension
B. Sieve tray towers are generally used for systems having low interfacial tension
C. When Henry’s law constant is very small, then the mass transfer rate is controlled by the gas
film resistance
D. Taylor-Prandtl analogy for heat and mass transfer considers the transfer through both laminar
and turbulent layers - Pick out the wrong statement?
A. Mass transfer co-efficient does not account for gas-liquid diffusion
B. Diffusion co-efficient and mass transfer co-efficient are not same in any mass transfer
operation
C. Contacting cold vapor-gas mixture with hot liquid exemplifies humidification process
D. Contacting cold liquid with warm vapor-gas mixture exemplifies dehumidification process - Pick out the wrong statement pertaining to the analogy between equations of heat and mass_________________?
transfer operations.
A. Sherwood number in mass transfer is analogous to Nusselt number in heat transfer
B. Prandtl number in heat transfer is analogous to Schmidt number in mass transfer
C. Reynolds number in mass transfer is analogous to Grashoff number in heat transfer
D. Reynolds number remains the same in both heat and mass transfer - Pick out the wrong statement?
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 - Pick out the wrong statement?
A. Change in barometric pressure does not affect the relative humidity
B. In case of a packed tower, the operating velocity is about half of the flooding velocity,
generally
C. ‘Elution’ means the desorption of the adsorbed solute by a solvent
D. The equilibrium moisture content of the solid can be reduced by increasing the absolute
humidity - Pick out the wrong statement ?
A. Constant pressure distillation cannot separate an Azeotropic mixture
B. Relative volatility of a binary mixture changes appreciably with the minor change in
temperature
C. The relative volatility of a binary mixture at Azeotropic composition is unity
D. Flash distillation is practised on wide spread scale in petroleum refinery - Pick out the wrong statement?
A. Packed towers are preferred for vacuum operation, because the pressure drop through the
packing is less and they (packings) also lessen the possibility of tower wall collapse
B. Packed towers are preferred over plate towers for handling corrosive and foamy liquids
C. Diameter of randomly packed tower is normally more than 1.2 metres
D. Due to uneven supply and improper distribution of liquid, problem of channelling, loading &
flooding is generally encountered in packed towers - Pick out the wrong statement?
A. In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated
liquid feed and horizontal feed line represents saturated vapour feed
B. In small columns, local efficiency is larger than Murphree efficiency; in large columns local
efficiency is smaller than Murphree efficiency
C. For Laminar flow over a plate of length L, the local mass transfer co-efficient at a distance L
from the leading edge is 1.5 × 10-2m/s. Then the average mass transfer co-efficient for the
plate is 2 × 10-2m/s
D. The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness,
if Schmidt number is equal to unity - Pick out the wrong statement ?
A. Cellulose acetate membranes are used in dialysis process
B. Elutriation process refers to when the soluble material is largely concentrated on the surface of
an insoluble solid and is simply washed off by the solvent
C. ‘Cascade’ means a group of stages interconnected so that various streams flow from one to
another
D. Zirconia probe is used for the humidity measurement - Pick out the wrong statement ?
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
