Mass Transfer Quiz 2

Batch tray dryers suffers from the disadvantage of________?

Boiling point diagram is not affected by the ambient________?

As complete saturation of an adsorbent is approached, the differential heat of adsrop-tion approaches ______?

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

Berl saddle made of carbon cannot be used for _____?

As per Gilliland?s equation, the diffusivity is_____?

Ammonia present in the coke oven gas is removed by washing with_____?

Can the efficiency of a plate in the distillation tower be greater than 100% ?

Blowdown in a cooling tower______?

At ___________ reflux, theoretical number of plates in a distillation coloumn is calculated using Fenske-Underwood equation?

Channelling in a packed tower results from the_______?

As the reflux ratio in a distillation column is increased from the minimum, the________?

Bound moisture is that liquid which exerts an equilibrium vapor pressure _________ that of the pure liquid at the given temperature ?

Condensation of a vapour-gas mixture just begins, when (where, p = partial pressure of the vapour P = vapour pressure of the liquid) ?

An example of elution is________?

Calcium ammonium nitrate (a fertiliser) is dried in a __________ dryer?

At 750?K and 1 atm, the approximate value of Schmidt number for air is__________?

Coffee is prepared from coffee beans by leaching with______?

At equilibrium the concentration of water in vapour phase (C*) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room of air space 100m3 containing 2.2 kg of water vapour initially, 10 kg of dry silica gel is kept in the room. The fraction of initial water remaining in the air space after a long time (during which the temperature is maintained constant) is__________?

An ideal tower packing should not _________?

An Azeotropic mixture is a _________ mixture?

At constant pressure, with increase of temperature, the dew point will __________?

At a fixed pressure, the humidity depends upon the partial pressure of vapor in the mixture. Humidity of a vapour free gas is _________ percent.?

Capacity of a rotary dryer depends on its ___________?

As the reflux ratio decreases, the__________?

CO2 can be absorbed by______?

Can the efficiency of a plate in the distillation tower be greater than 100% ?

Below is given an equilibrium moisture curve of a substance. State which regions represent free moisture and unbound moisture respectively ?

Ammonia present in the coke oven gas is removed by washing with_____?

At minimum reflux ratio for a given separation___________?

Channelling is most severe_______?

Co-current absorbers are usually used when the gas to be dissolved in the liquid is _____?

Corresponding to Prandtl number in heat transfer, the dimensionless group in mass transfer is the ________ number?

Calculation of mass transfer co-efficient is mostly/normally done using _______ theory?

At what percentage (by volume) of alcohol composition, it forms an azeotrope with water ?

Blowdown in a cooling tower___________?

At a fixed total pressure, humidity depends only on the _________?

Bollman extractor_____?

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) ______?

Corresponding to Nusselt number in heat transfer, the dimensionless group in mass transfer is the _________ number?

At a given equilibrium pressure, with increase in temperature, the concentration of adsorbed gas on solid adsorbent ___________?

Azeotropism for ethyl alcohol-water system disappears by_______?

Back-trapping in a distillation column ?

At the boiling point of the liquid at the prevailing pressure, the saturated absolute humidity becomes_______?

Binary distillation involves the mass transfer by ________ at the gas-liquid interface?

All moisture in a non-hygroscopic material is the _________ moisture?

Compound A is extracted from a solution of A + B into a pure solvent S. A Co-current unit is used for the liquid-liquid extraction. The inlet rate of the solution containing A is 200 moles of B/hr.m2 and the solvent flow, rate is 400 moles of S/m2. hr. The equilibrium data is represented by Y = 3X2 , where Y is in moles of a A/moles of B and X is in moles A/moles of S. The maximum percentage extraction achieved in the unit is___________?

Can a cooling tower cool water below the wet bulb temperature of inlet air ?

At the boiling point of the liquid at the prevailing pressure, the saturated absolute humidity becomes________?

At the same gas flow rate, the pressure drop in a packed tower being irrigated with liquid ________ that in dry packed tower ?