Practice Test: Question Set - 17
1. 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
2. According to Chilton-Colburn analogy for mass transfer, NSt.NSc2/3 is equal to
- (A) f
- (B) f/2
- (C) 2f
- (D) 1/f
3. 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
4. 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
5. Separation of the isotopes of helium for scientific investigations is done by
- (A) Reverse osmosis
- (B) Thermal diffusion
- (C) Leaching
- (D) Solvent extraction
6. 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
7. The McCabe ΔL law states that the
- (A) Molar heats of
vaporization of components are nearly equal
- (B) Linear crystal growth
rate depends on the degree of super-saturation
- (C) Linear crystal growth
rate does not depend on the crystal size
- (D) Linear crystal growth
rate depends on the crystal size
8. When both the fluids flow concurrently in an absorber, the slope of the operating line is
- (A) -ve
- (B) +ve
- (C) 1
- (D) -1
9. 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)
10. The relative saturation of a partially saturated mixture of vapor and gas can be increased by __________ of the mixture.
- (A) Reducing the total
pressure
- (B) Increasing the total
pressure
- (C) Reducing the
temperature
- (D) Both (b) and (c)
11. 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
column
- (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
12. 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 practiced on wide spread scale in petroleum refinery
13. Which of the following is the correct ternary diagram for liquid-liquid extraction system comprising of two pairs partly soluble (e.g., chlorobenzene-water-methyl ethyl ketone system)?
14. 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
15. __________ diffusion is used for separating the isotopes of methane.
- (A) Thermal
- (B) Pressure
- (C) Concentration
- (D) Force
Blogger Comment
Facebook Comment