Q. Acetone is to be removed from air in an isothermal dilute absorber using pure water as solvent. The incoming air contains 5 mole% of acetone (yin = 0.05). The design equation to be used for obtaining the number of trays (N) of the absorber is, N+2 = 6 log (yin/yout).For 98% recovery of acetone, the number of trays required is/are

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Q. Schimdt number and Lewis number for pure air at atmospheric conditions are respectively

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Q. Molecular diffusion is caused by the

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Q. At __________ reflux, theoretical number of plates in a distillation coloumn is calculated using Fenske-Underwood equation.

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Q. Separation of a mixture of two gases by absorption in the liquid solvent depends upon the difference in their

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Q. Components, having widely different boiling point in a binary mixture, can be separated using __________ distillation.

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Q. Which of the following equipments is not used in liquid-liquid extraction ?

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Q. Pick out the wrong statement.

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Q. Nitrobenzene (boiling point = 210.6°C) is steam distilled at 1 atm pressure.Nitrobenzene will distill off __________ °C.

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Q. Pick out the wrong statement.

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Q. At what value of reflux ratio, number of theoretical plates in a distillation column is minimum ?

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Q. Batch tray dryers suffers from the disadvantage of

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Q. In a moderately sized packed absorption tower, channeling (which is most severe with stacked packings) can be minimised by taking the ratio of tower diameter to packing diameter

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Q. An alkaline solution is used to reduce the concentration of carbon dioxide in a stream from 10% to 0.1% by absorption with irreversible chemical reaction. The overall number of transfer units based on gas phase is

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Q. HETP is numerically equal to HTU, only when the operating line

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Q. 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.

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Q. Steady state equimolal counter diffusion occurs in case of

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Q. 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

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Q. Use of packed towers for distillation is generally limited to the

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Q. Pick out the wrong statement.

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