Mass Transfer Mcqs
This set of Engineering Multiple Choice Questions & Answers (MCQs) focuses on “ Mass Transfer ”. These Mcqs are chosen from a collection of most authoritative and best reference books on Chemical Engineering. Our aim is to prepare an individual for competitive exams like NTS, GAT, ECAT, University and College entrance exams, Jobs and interviews. One should practice our MCQS to assimilate Mass Transfer comprehensively.
32. For a vapour-gas mixture the wet and dry-bulb temperature are 20?C and 35?C respectively if the mixture is heated to 50?C at constant pressure the wet bulb temperature will be
20?C
>20?C
<20?C
? 20?C
33. At the boiling point of the liquid at the prevailing pressure the saturated absolute humidity becomes
One
Zero
Infinity
None of the above
Answer & Solution
No Solution for this Answer..! Report or Discus this Question
34. The dew point of an unsaturated mixture of water vapour and air at constant temperature and pressure
Does not change with change in absolute humidity
Increases with increase in absolute humidity
Decreases with increase in absolute humidity
Decreases linearily with increase in absolute humidity.
Answer & Solution
No Solution for this Answer..! Report or Discus this Question
35. The steady-state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called
Dry-bulb temperature
Dew point
Wet-bulb temperature
Bubble point
Answer & Solution
No Solution for this Answer..! Report or Discus this Question
36. For any vapour-gas mixture the adiabatic saturation curve is
Straight line
Slightly concave upward
Slightly concave downward
B
37. The psychrometric ratio is defined as
HG/ky
Ky/hG
HG/ky Cs
NSc/NPr
38. The Lewis number of a mixture is defined as
NPr/NSc
NPr NSc
NSc/NPr
Cs (NSc/NPr)
39. For the system air-water vapour hG/ky Cs is approximately equal to
1
0.24
2.4
3
40. The lewis number of a mixture is one when mass diffusivity is equal to
Momentum diffusivity
Thermal diffusivity
Thermal conductivity
1/thermal diffusivity
Answer & Solution
No Solution for this Answer..! Report or Discus this Question
41. For pure air at atmospheric conditions the Lewis number is
<<1
>>1
?
?
42. For pure air at atmospheric conditions the Schmidt number is
<1
1
>1
>>1
43. The temperature of water cooled in a cooling tower is
Always less than the wet-bulb temperature of entering air
Always equal to the wet-bulb temperature of entering air
Always greater than the wet-bulb temperature of entering air
Always equal to the dry-bulb temperature of entering air.
Answer & Solution
No Solution for this Answer..! Report or Discus this Question
44. In the design of cooling towers the wet-bulb temperature approach is ordinarily specified to be
From 5 to 10?F
From 20 to 30?F
From 30 to 35?F
From 10 to 25?F
Answer & Solution
No Solution for this Answer..! Report or Discus this Question
45. In a cooling tower makeup fresh water must be added to replace losses from
Entrainment
Evaporation losses
Blowdown
All of the above
Answer & Solution
No Solution for this Answer..! Report or Discus this Question