Top 550+ Solved Mass Transfer MCQ Questions Answer
Q. __________ is the separation technique used for desalination of sea water.
a. Thermal diffusion
b. Reverse osmosis
c. Adsorption
d. Absorption
Q. The partial pressure distribution of an ideal gas diffusing through another stagnant idealgas at steady state follows a/an __________ law.
a. Exponential
b. Parabolic
c. Linear
d. Cubic
Q. Out of two equilibrium curves, first one lies above the diagonal and the second lies below the diagonal in the x-y plot. It means that separation by distillation is
a. Not possible in the second case unless vacuum is applied
b. Not possible in the second case unless high pressure is applied
c. More readily done in the second case compared to first one
d. None of these
Q. According to Chilton-Colburn analogy for mass transfer, NSt.NSc 2/3 is equal to
a. f
b. f/2
c. 2f
d. 1/f
Q. Very tall packed towers are divided into series of beds to
a. Reduce the overall pressure drop
b. Avoid channelling
c. Reduce liquid hold-up
d. Avoid flooding
Q. If „f’ is defined as above, then which of the following applies to a feed at dew point?
a. f = 1
b. f < 1
c. f > 1
d. 0 < f < 1
Q. Separation of the isotopes of helium for scientific investigations is done by
a. Reverse osmosis
b. Thermal diffusion
c. Leaching
d. Solvent extraction
Q. Flash distillation is suitable for the separation of components
a. Having very close boiling points
b. Which form maximum boiling azeotrope
c. Having very wide boiling points
d. Which form minimum boiling azeotrope
Q. When both the fluids flow concurrently in an absorber, the slope of the operating line is
a. -ve
b. +ve
c. 1
d. -1
Q. Steam distillation is used for separation of high boiling
a. Substances from non-volatile impurities
b. Volatile impurity from still higher boiling substances
c. Both (A) and (B)
d. Neither (A) nor (B)
Q. The relative saturation of a partially saturated mixture of vapour and gas can be increasedby __________ of the mixture.
a. Reducing the total pressure
b. Increasing the total pressure
c. Reducing the temperature
d. Both (B) and (C)
Q. Pick out the correct statement.
a. Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of non-ideal binary system by distillation
b. A sharp decrease in pressure drop is an indication of flooding in a distillation coloumn
c. Solvent used in extractive distillation should be of high volatility
d. Flash distillation is suitable for separating components which have very close boiling temperature
Q. 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
Q. 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. Remain unaffected
d. Passes through a maximum
Q. __________ diffusion is used for separating the isotopes of methane.
a. Thermal
b. Pressure
c. Concentration
d. Force