Home→ Mass Transfer →Mass transfer co-efficient is defined as__________________?

Large quantity of silica gel is normally dried in a __________ dryer?
The value of „L/mG’ ratio for economical absorption operation ranges from __________?
In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raffinate phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass of the extract phase is (in Kg) ?
Dried finished product sampled from various parts of a __________ dryer exhibits nonuniformity in the moisture content?
In steam distillation, the __________?
A slurry is to be dried to produce flaky solid. Which dryer would you recommend ?
Which of the following parameters remains constant during chemical dehumidification ?
Coffee is prepared from coffee beans by leaching with__________?
The equation, NA = (DAB . Pt /RTZ) (y1 – y2) is for __________?
Penetration theory states that the mass transfer co-coefficient is equal to (where, De is diffusivity and ‘t’ is time) ?
The relative volatility of a binary mixture at the Azeotropic composition is __________?
For absorbing a sparingly soluble gas in a liquid, the__________?
Moisture content of a substance when at equilibrium with a given partial pressure of the vapour is called the __________ moisture?
For the flow of gases through a capillary, with increase in temperature, the permeability __________ as per Knudsen law?
With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop__________?
A natural draft cooling tower is filled with wooden grids, which covers about __________ percent of the tower height?
The Knudsen diffusivity is proportional to (where, T = absolute temperature) __________?
Which of the following processes is not an example of adsorption applied to gaseous separations ?
The cooling effect in a cooling tower can be speeded up by __________?
To remove all the moisture from a wet solid it requires exposure to __________ air?
Pore size of the molecular sieve 5A is __________ mm ?
For the gas absorption, the height of a transfer unit, based on the gas phase is given by (G: superficial molar gas velocity, L: superficial molar liquid velocity, FG: mass transfer co-efficient, moles/m2, a: interfacial area per unit volume of tower) ?
Perforated plate towers are unique for solvent extraction because, they provide__________?
The equation, NA = (DAB . Pt /RTZ . PBM) (PA1 – PA2) is for__________?
For the same system, if the same liquid used in an absorber is decreased, the tower height will__________?
The commonly used solvent in supercritical extraction is__________?
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) ?
The mass transfer co-efficient for a solid sphere of radius ‘a’ dissolving in a large volume of quiescent liquid, in which „D’ is the diffusivity of solute, is __________?
The relative volatility of a binary mixture at constant temperature __________ the total pressure?
__________ equation applies to diffusivities in liquids?
When the gas to be dissolved in liquid is a/an __________ then normally co-current adsorber are used?
Experiments were conducted to determine the flux of a species A in a stagnant medium across a gas-liquid interface. The overall mass transfer co-efficient based on the liquid side for dilute systems for the above was estimated to be 4 × 10-3 kg mole/m2.s. The equilibrium data for the system is given as y = 2x. The flux across the interface (in kg mole/m2 .s) for bulk concentrations of A in gas phase and liquid phase as y = 0.4 and x = 0.01 respectively is __________?
H2S is being absorbed in a gas absorber unit. The height of the transfer unit based on the overall mass transfer coefficient on the gas side is 0.4 m. The equilibrium data is given by, y = 1.5 x. The bulk concentration of H2S has to be reduced from 0.05 to 0.001 mole fraction in the gas side. The height of the tower (in meters) corresponding to an operating line given by, y = 5x + 0.001 is __________?
Large scale drying of sugar is done in a __________ dryer?
As the reflux ratio, in a continuous counter-current extraction is increased, the number of stages__________?
Humidification involves mass transfer between a pure liquid phase and a fixed gas, which is__________?
During the constant rate period of drying of a solid ?
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 ?

Mass transfer co-efficient is defined as__________________?

A. Flux = Co-efficient/concentration difference
B. Co-efficient = Flux/concentration difference
C. Flux=concentration difference/coefficient
D. None of these

Correct Answer: Co-efficient = Flux/concentration difference ✔

Last Updated: February 15, 2019