231. Operating velocity in a packed tower is usually __________ the flooding velocity.
Half
Twice
Equal to
More than
✅ The correct answer is option A.
Mass Transfer MCQs
232. Refractory bricks are usually dried in a __________ dryer.
Tray
Tunnel
Conveyor
Festoon
✅ The correct answer is option B.
233. In saturated gas, the
Vapour is in equilibrium with the liquid at the gas temperature
Vapour is in equilibrium with the liquid at the room temperature
Partial pressure of vapour equals the vapour pressure of the liquid at room temperature
None of these
✅ The correct answer is option A.
234. The commonly used solvent in supercritical extraction is
Methyl ethyl ketone
Water
Carbon tetrachloride
Carbon dioxide
✅ The correct answer is option D.
235. An ideal tower packing should not
Have low weight per unit volume
Have large surface area per unit volume
Have large free cross-section
Hold up large amount of liquid in the packing
✅ The correct answer is option D.
236. In a binary system, separation is very efficient, when the relative volatility is
1
> 1
< 1
0.5
✅ The correct answer is option B.
237. Raschig ring made of procelain cannot be used for treating concentrated
Hydrochloric acid
Nitric acid
Alkalis
Sulphuric acid
✅ The correct answer is option C.
239. Condensation of a vapour-gas mixture just begins, when (where, p = partial pressure of the vapour P = vapour pressure of the liquid )
P = P
P >>P
P < P
P << P
✅ The correct answer is option A.
240. A solid material shows case hardening properties while drying. Which of the following should be controlled to control the drying process?
Flow rate of inlet air
Relative humidity of outlet air
Humidity of inlet air
Temperature of the solid
✅ The correct answer is option D.