391. __________ is used as an ‘entrainer’ for the separation of acetic acid-water mixture by distillation.
Furfural
Benzol
Butyl acetate
Hexane
✅ The correct answer is option C.
Mass Transfer MCQs
392. Stage efficiency in a leaching process depends on the
Time of contact between the solid and the solution
Rate of diffusion of the solute through the solid and into the liquid
Both A & B
Vapour pressure of the solution
✅ The correct answer is option C.
393. Large quantity of silica gel is normally dried in a __________ dryer.
Freeze
Through circulation
Rotary vacuum
Tray
✅ The correct answer is option B.
394. Extraction of coffee from its seed is done by
Liquid-liquid extraction
Leaching
Extractive distillation
Steam distillation
✅ The correct answer is option B.
395. Absorption factor is defined as (where, S₁ = slope of the operating line S₂ = slope of the equilibrium curve)
S₂/S₁
S₁/S₂
S₁ – S₂
S₁ x S₂
✅ The correct answer is option B.
396. 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 coloumn.
5
9
12
28
✅ The correct answer is option C.
397. (NRe . NSc) is termed in mass transfer operation as the __________ number.
Stanton
Sherwood
Peclet
None of these
✅ The correct answer is option C.
398. An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively.The humidity of air sample expressed as kg of water vapour/kg of dry air is
0.048
0.079
0.122
0.152
✅ The correct answer is option D.
399. The equipment used in the extraction of highly corrosive radio active liquids is
Pulse column
Spray column
Mixer settler
Baffle tower
✅ The correct answer is option A.
400. Rose oil is extracted from rose leaves using __________ distillation.
High pressure
Low pressure
Extractive
Steam
✅ The correct answer is option D.