Related Mcqs:

1. In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions: (i) Reflux stream is completely liquid and is at its bubble point. (ii) Reflux stream is below its bubble point ?

   A. Condenser and reboiler loads are the same in both the cases
   B. Reboiler load is the same in both the cases but condenser load is higher in case (ii)
   C. Condenser load is the same in both the cases but reboiler load is higher in case (ii)
   D. Both condenser and reboiler loads are higher in case (ii) as compared to case (i)

2. In a gas-liquid absorption column, for obtaining the maximum absorption efficiency____________________?

   A. Liquid stream should be distributed uniformly
   B. Gas stream should be distributed uniformly
   C. Both gas as well as liquid streams should be distributed uniformly
   D. By passing should be completely avoided
   Answer: Option C

3. Even though bubble cap towers are very effective for humidification operation, they are not used commonly in industries, because of the_________________?

   A. High evaporation losses of water
   B. High pressure drop of the gas
   C. Difficulty in its fabrication
   D. None of these

4. According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B ? Assume that relative volatility (αAB = 2) does not change appreciably in the column ?

   A. 5
   B. 9
   C. 12
   D. 28

5. Packed column distillation is limited to the column _____________ metres?

   A. Height < 6
   B. Diameter < 0.6
   C. Both A. & B.
   D. Neither A. nor B.

6. A distillation column with N plates is being operated under normal conditions. At some point of time, the operation is shifted to total reflux condition (i.e., no product and residue are being withdrawn and feed to the column is stopped). At the new steady state ?

   A. Composition of vapors and that of liquid do not vary throughout the column
   B. Reboiler load and condenser load are minimum
   C. The top and bottom compositions are unchanged with and without total reflux
   D. The top and bottom compositions correspond to the maximum enrichment available

7. Cox chart, which is useful in the design of distillation column particularly for petroleum hydrocarbons, is a plot of (where, P = vapor pressure, T = temperature) ?

   A. log P vs. T
   B. log P vs. log T
   C. T vs. P
   D. P vs. log T

8. An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are being explored; (i) a reboiler is used and (ii) no reboiler is used but steam is fed directly to the bottom of the column. As compared to option (i), in option (ii) ____________________?

   A. Less number of trays are required
   B. Composition of the residue remains unchanged
   C. More number of trays are required but the residue composition remains unchanged
   D. More number of trays are required and the residue composition is more dilute in methanol

9. In distillation columns, the number of bubble caps per tray primarily depends upon the_______________________?

   A. Allowable liquid velocity
   B. Allowable gas velocity
   C. Allowable gas and liquid velocities
   D. Feed composition

10. Polar organic compounds are normally used as separating agents for the azeotropic and extractive distillation. Which of the following is the most important factor to be considered for the choice of the separating agent for extractive distillation ?

    A. Cost
    B. Availability
    C. Toxicity
    D. Selectivity