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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Q. Which of the following decreases during evaporative cooling process with recirculated water supply ?

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Q. Laboratory determination of the diffusivity of vapor is done by __________ method.

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Q. The minimum liquid rate to be used in an absorber corresponds to an operating line

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Q. 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

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Q. According to Chilton-Colburn analogy for mass transfer, (NSt.NSc)^2/3 is equal to

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Q. A pure drug is administered as a sphere and as a cube. The amount of drug is the same in the two tablets. Assuming that the shape and size do not influence the mass transfer, the ratio of rate of dissolution in water at t = 0 for the cubic to spherical tablet is

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Q. Minimum reflux ratio in a distillation column results in

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Q. Flooding in a distillation column is detected by a sharp

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Q. In case of unsaturated air

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Q. For a binary mixture with low relative volatility,

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Q. Plate efficiency

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Q. Absorption accompanied by heat evolution results in

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