271. In a packed bed absorption column, the channelling will be noted by the
Increase in flow rate
Sharp drop in pressure drop
Sharp rise in pressure drop
None of these
✅ The correct answer is option B.
Mass Transfer MCQs
272. Henry’s law states that the
Partial pressure of a component over a solution is proportional to its mole fraction in the liquid
Partial pressure of a component over a solution is proportional to the mole fraction in the vapour
Vapour pressure is equal to the product of the mole fraction and total pressure
Partial pressure is equal to the product of the mole fraction and total pressure
✅ The correct answer is option A.
273. Which of the following liquid-vapor contacting devices provides maximum contact surface area for a particular duty?
Sieve plate column
Bubble cap column
Randomly packed column
Wetted wall column
✅ The correct answer is option D.
274. For absorbing a sparingly soluble gas in a liquid
Gas side mass transfer co-efficient should be increased
Liquid side mass transfer co-efficient should be increased
Liquid side mass transfer co-efficient should be decreased
Mass transfer co-efficient must be kept constant
✅ The correct answer is option B.
275. When the psychometric ratio is __________ then the adiabatic saturation temperature and wet bulb temperature becomes equal.
1
< 1
> 1
?
✅ The correct answer is option A.
276. 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)
Less number of trays are required
Composition of the residue remains unchanged
More number of trays are required but the residue composition remains unchanged
More number of trays are required and the residue composition is more dilute in methanol
✅ The correct answer is option A.
277. The minimum liquid rate to be used in an absorber corresponds to an operating line
Of slope = 1
Ofslope = 0.1
Tangential to the equilibrium curve
None of these
✅ The correct answer is option C.
278. If the specific heats of a gas and a vapor are 0.2KJ/Kg.°K and 1.5 KJ/Kg.°K respectively, and the humidity is 0.01; the humid heat in KJ/°Kg. is
0.31
0.107
0.017
0.215
✅ The correct answer is option D.
279. Molecular distillation is
High temperature distillation
For heat-sensitive materials
Very low pressure distillation
Both B and C
✅ The correct answer is option D.
280. When the __________ the relative humidity of air decreases, despite an increase in the absolute humidity.
Temperature rises
Pressure rises
Temperature falls
Pressure falls
✅ The correct answer is option A.