The cooling effect in a cooling tower can be increased by
A.lowering the barometric pressure
B.reducing the humidity of entering air
C.increasing the air velocity over the wet surfaces
D.all of the above
Category: Mass Transfer Mcqs
The flooding in a distillation column is detected by
A.a sharp increase in pressure drop
B.a sharp increase in Murphree plate efficiency
C.a sharp decrease in pressure drop
D.a sharp decrease in liquid hold up in the column
Azeotropes
A.are mixtures with constant boiling point at the specified pressure
B.obey Raoults law at all temperature
C.are mixtures of partially miscible liquids
D.none of the above
The psychrometric ratio is defined as
A.hG/ky
B.ky/hG
C.hG/ky Cs
D.NSc/NPr
Under the same conditions
A.1 m3 of dry air is lighter than 1 m3 of humid air
B.1 m3 of humid air is lighter than 1 m3 of dry air
C.both 1 m3 of dry air and 1 m3 of humid air have the same weight
The binary diffusivity in gases at atmospheric conditions is of the order of
A.10-1 cm2/sec
B.10-5 cm2/sec
C.105 cm2/sec
D.10-7 cm2/sec
Entrainment in a distillation column
A.is defined as the liquid carried with the vapour from one tray to the tray above
B.is detected by decrease in Murphree plate efficiency
C.may be detrimental since it can carry non-volatile constituents upward
D.all of these answers
