Practice Test: Question Set - 28
1. The expression, ln(F/W) = ∫xFxW [dx/y* - x)] is
- (A) Differential
distillation equation
- (B) For NtoG in
absorption for dilute mixture
- (C) Slope of q-line
in McCabe-Thiele method
- (D) For relative
volatility
2. Wetted wall tower experiment determines the
- (A) Molal diffusivity
- (B) Volumetric
co-efficient
- (C) Mass transfer
co-efficient
- (D) None of these
3. Condensation of a vapor-gas mixture just begins, when (where, p = partial pressure of the vapor P = vapor pressure of the liquid).
- (A) p = P
- (B) p >>P
- (C) p < P
- (D) p << P
4. If the overall efficiency and Murphree plate efficiency are equal, then both the equilibrium and operating lines are:
- (A) Straight
- (B) Parallel
- (C) Both (a) & (b)
- (D) Neither (a) nor (b)
5. JD factor for mass transfer is a function of Reynolds number. Mass transfer by molecular diffusion from a single drop to surrounding still air is given by
- (A) Nsh = 2
- (B) Nst = 2
- (C) Nsc = 2
- (D) None of these
6. In liquid-liquid extraction, the number of phases at plait point is
- (A) 1
- (B) 2
- (C) 3
- (D) 4
7. Molecular sieves are porous
- (A) Alumina
- (B) Silica
- (C) Synthetic zeolites
crystals/metal alumino-silicates
- (D) None of these
8. Nitrobenzene (boiling point = 210.6°C) is steam distilled at 1 atm pressure. Nitrobenzene will distil off __________ °C.
- (A) At < 100
- (B) At > 210.6
- (C) Between 100 and 210
- (D) None of these
9. Selectivity of the solvent used in solvent extraction should be
- (A) 1
- (B) > 1
- (C) < 1
- (D) 0
10. The relative humidity of air decreases in-spite of an increase in the absolute humidity, when the
- (A) Temperature rises
- (B) Pressure rises
- (C) Temperature falls
- (D) Pressure falls
11. The dew point of a saturated gas phase equals the __________ temperature.
- (A) Gas
- (B) Room
- (C) Wet bulb
- (D) None of these
12. The amount of steam required per unit quantity of distillate in case of steam distillation will be reduced by
- (A) Raising the
temperature
- (B) Lowering the total
pressure
- (C) Both (a) and (b)
- (D) Neither (a) nor (b)
13. Priming in a distillation column
- (A) Results from very low
gas velocity
- (B) Is desirable from
point efficiency consideration
- (C) Is characterized by
the presence of foam throughout the space between trays
- (D) Reduces
the overall pressure drop
14. Separation of a mixture of two gases by absorption in the liquid solvent depends upon the difference in their
- (A) Viscosity
- (B) Density
- (C) Solubility
- (D) Relative volatility
15. The efficiency of a plate column will be maximum, when the flow is ideal __________ the plate.
- (A) Across
- (B) Above
- (C) Both (a) & (b)
- (D) Neither (a) nor (b)
Next Tests: