Home
About Us
Contact Us
Privacy Policy
Search
Home
→
Mass Transfer
→
The rough value of diffusion co-efficient of water vapor into air at 25°C may be about ______________ cm2/sec?
Related MCQs
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 ?
__________ column is used in gas absorption process ?
The diffusion co-efficient in m2/s. of acetic acid in benzene (liquid in liquid) is__________?
The ‘shanks system’ of leaching (i.e., counter-current multiple contact leaching) is used for__________?
Which of the following employs an accessory known as ‘drift eliminator’ ?
The term “approach” in a cooling tower refers to the difference in the temperature of the__________?
Below is given an equilibrium moisture curve of a substance. State which regions represent free moisture and unbound moisture respectively ?
Humid volume, at a given temperature is a/an __________ function of humidity?
Flooding in a vapor-liquid contacting equipment occurs in a tray, when the pressure drop through a tray is __________ the liquid head available in the downcomer?
Which of the following is an undesirable characteristic for the solvent used in gas absorption ?
For the same feed, feed quality and separation (in a distillation column), with the increase of total pressure, the number of ideal plates will__________?
A liquid mixture contains 30% o-xylene, 60% p-xylene and 10%. m-xylene (all percentages in w/w). Which of the following statements would be true in respect of this mixture ?
In case of binary distillation, increasing the reflux ratio above optimum does not result in the increase of__________?
Which of the following assumes constant molal vaporisation and overflow ?
Which of the following binary systems is an example of a maximum boiling azeotrope ?
Channelling is most severe__________?
Extraction of coffee from its seed is done by__________?
When the liquid phase and vapour phase of a binary system obeys Raoult’s and Dalton’s law respectively, the relative volatility is the ratio of__________?
Flooding in a column results due to__________?
Raoult’s law is applicable to the__________?
Calcium ammonium nitrate (a fertiliser) is dried in a __________ dryer?
Pick out the system with minimum boiling azeotrope at 1 atm ?
The film penetration model of mass transfer was enunciated by__________?
(NRe . NSc) is termed in mass transfer operation as the __________ number?
In McCabe-Thiele method, at infinite reflux ratio__________?
With lapse of time, the overhead composition of light component in case of batch distillation with constant reflux__________?
The operation involved when the soluble material is largely on the surface of an insoluble solid and is merely washed off by the solvent is called__________?
The recovery of penicillin from the acidified fermentation broth is done by__________?
Absorption factor, for a fixed degree of absorption from a fixed amount of gas should be__________?
Molarity is defined as the number of gm moles of solute per __________ of solvent?
Adsorption is a unit operation which generally involves __________ systems?
Agitator is provided in a crystalliser for__________?
Lewis number, which is important in problems involving simultaneous heat and mass transfer, is the ratio of__________?
Corresponding to Nusselt number in heat transfer, the dimensionless group in mass transfer is the __________ number?
Cox chart is useful in the design of__________?
The binary diffusivity in gases and liquids vary respectively as__________?
Decoction refers to the use of solvent__________?
Ordinary diffusion process is also called __________ diffusion?
Out of the following gas-liquid contacting devices, for a given set of operating conditions, gas pressure drop is the least in __________ tower?
The solvent used in liquid-liquid extraction should have __________ less than one?
Which of the following equipments is not used for liquid dispersion ?
Diffusion co-efficient generally depends upon the temperature, pressure & the nature of the components of the system. Its dimension is not the same as that of the__________?
Schmidt number and Lewis number for pure air at atmospheric conditions are respectively__________?
The falling rate period in the drying of a solid is characterised by__________?
Azeotropism for ethyl alcohol-water system disappears by__________?
In a liquid-liquid extraction, 10 kg of a solution containing 2 kg of solute C and 8 kg of solvent A is brought into contact with 10 kg of solvent B. Solvent A and B are completely immiscible in each other whereas solute C is soluble in both the solvents. The extraction process attains equilibrium. The equilibrium relationship between the two phases is Y* = 0.9X, where Y* is the kg of C/kg of B and X is kg of C/kg of A. Choose the correct answer?
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 ?
Sand is dried in foundries in a __________drier?
Binary distillation involves the mass transfer by __________ at the gas-liquid interface?
Which of the following adsorbent is used to decolourise yellow glycerine ?
Surface renewal model of mass transfer was enunciated by__________?
The rough value of diffusion co-efficient of water vapor into air at 25°C may be about ______________ cm2/sec?
A. 0.25
B. 2.5
C. 1.25
D. 0.0025
Correct Answer:
0.25
✔
Last Updated:
February 17, 2019