Mass Transfer Basic Interview Questions and Answers - Set 05 - ObjectiveBooks

# Practice Test: Question Set - 05

1. For stripping of a gas in a counter current stripper, the operating line
(A) Lies above the equilibrium curve
(B) Lies below the equilibrium curve
(C) Can lie above or below the equilibrium curve
(D) Is always parallel to the equilibrium curve

2. The Reynolds number of the liquid was increased 100 fold for a laminar falling film used for gas-liquid contacting. Assuming penetrating theory is applicable, the fold increase in the mass transfer co-efficient (Kc) for the same system is.
(A) 100
(B) 10
(C) 5
(D) 1

3. The boiling points of pure components of a binary system __________ with increase in total pressure of the system.
(A) Decreases
(B) Increases
(C) Remains unchanged
(D) May increase or decrease, depends on the system

4. In gas-liquid contact operation, the number of ideal stages, N = (xa - xb)/(xb - x*b). This is true when the stripping factor 'S' is
(A) S > 1
(B) S < 1
(C) S = 1
(D) S = ∞

5. Large scale usage of flash distillation is practiced in
(A) Soap manufacturing
(B) Ammonia synthesis plant
(C) Polymerization industry
(D) Petroleum refining

6. Drying of a solid involves __________ transfer.
(A) Only heat
(B) Only mass
(C) Both heat and mass
(D) None of these

7. Desulphurisation of petrol is done in a
(A) Bollman extractor
(B) Rotating disc extractor
(C) Packed extraction column
(D) Plate type extraction column

8. Pick out the wrong statement
(A) Co-current absorbers are usually used, when the gas to be dissolved in the liquid is a pure substance
(B) In case of gas absorption, HETP is equal to HTU, when both the operating line & the equilibrium lines are parallel
(C) Hatta number is important in case of gas absorption with chemical reaction
(D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process

9. Which of the following increases during evaporative cooling process with recirculated water supply?
(A) Wet bulb temperature
(B) Relative humidity
(C) Partial pressure of vapor
(D) Both (b) and (c)

10. Operating velocity in a packed tower is usually __________ the flooding velocity.
(A) Half
(B) Twice
(C) Equal to
(D) More than

11. For gas absorption, low viscosity solvents are preferred, because of their
(A) Better flow characteristics
(B) Low pumping pressure drop
(C) Rapid absorption rates
(D) All (a), (b) and (c)

12. Which of the following is used for the concentration of rubber latex?
(A) Agitated film evaporator
(B) Long tube vertical evaporator
(C) Short tube evaporator
(D) Calandria

13. Pressure drop through plate tower as compared to that through packed tower, for the same duty will be
(A) Less
(B) More
(C) Equal
(D) Either (a) or (b); depends on the packing height

14. In case of absorption & stripping, the interface of the liquid & gas phases are present in equilibrium, when the diffusional resistance of __________ is zero.
(A) Interface
(B) Gas phase
(C) Liquid phase
(D) All 'a', 'b' & 'c'

15. Henry's law states that the
(A) Partial pressure of a component over a solution is proportional to its mole fraction in the liquid
(B) Partial pressure of a component over a solution is proportional to the mole fraction in the vapour
(C) Vapor pressure is equal to the product of the mole fraction and total pressure
(D) Partial pressure is equal to the product of the mole fraction and total pressure

Show and hide multiple DIV using JavaScript View All Answers

Next Tests:
Blogger Comment