Top 550+ Solved Mass Transfer MCQ Questions Answer
Q. Bound moisture is that liquid which exerts an equilibrium vapor pressure __________ that of the pure liquid at the given temperature.
a. Less than
b. More than
c. Equal to
d. Either (A) or (B); depends on the solid
Q. Which of the following is not a batch drier?
a. Truck drier
b. Agitated pan drier
c. Fluidised bed drier
d. Vacuum shelf drier
Q. Acetic acid will be most economically separated from a dilute solution of acetic acid in water by
a. Solvent extraction
b. Continuous distillation
c. Evaporation
d. Absorption
Q. The main reason for dividing a tall packed tower into series of small towers is to
a. Minimise the overall pressure drop
b. Avoid flooding
c. Reduce liquid hold up
d. Avoid channelling
Q. The most efficient cooling tower out of the following is
a. Induced draft
b. Forced draft
c. Natural draft
d. Atmospheric
Q. Molecular distillation is
a. High temperature distillation
b. For heat-sensitive materials
c. Very low pressure distillation
d. Both (B) and (C)
Q. All moisture in a non-hygroscopic material is the __________ moisture.
a. Free
b. Equilibrium
c. Unbound
d. Bound
Q. 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
Q. Raschig ring made of porcelain cannot be used for treating concentrated
a. Hydrochloric acid
b. Nitric acid
c. Alkalis
d. Sulphuric acid
Q. Use of natural draft cooling tower is practised, when the air has low
a. Humidity
b. Temperature
c. Both 'a' & 'b'
d. Neither 'a' nor 'b'
Q. At a fixed pressure, the humidity depends upon the partial pressure of vapor in the mixture. Humidity of a vapour free gas is __________ percent.
a. 100
b. zero
c. 50
d. Between 0 and 100
Q. Tower diameter may be decreased by
a. Using higher reflux ratio
b. Use of increased tray spacing
c. Increasing the liquid flow rate
d. Increasing the vapour flow rate
Q. Pick out the wrong statement.
a. The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are the same for NSc = NPr= 1
b. 1 Nm3 of dry air is lighter than 1Nm3 of humid air
c. The Lewis number of a mixture is unity, when the thermal diffusivity is equal to the mass diffusivity
d. An Azeotropic mixture of two liquids has boiling point higher than either of them, when it shows negative deviation from Raoult's Law
Q. The humid volume may be increased by increasing the
a. Temperature at constant humidity
b. Humidity at constant temperature
c. Both (A) and (B)
d. Neither (A) nor (B)