Reduce the number of plates
Avoid thermal decomposition of a component
Increase the efficiency of separation
Increase the total pressure of distillation
✅ The correct answer is option B.
Mass Transfer MCQs
112. McCabe-Thiele method
Uses molal units for material and energy balance
Uses weight fractions to express liquid and vapour composition
Can use any type of units
Is more accurate than Ponchan-Savarit method
✅ The correct answer is option A.
113. In liquid-liquid extraction, the number of phases at plait point is
1
2
3
4
✅ The correct answer is option A.
114. Which of the following gas-liquid contacting devices incurs the least pressure drop for a particular duty?
Grid tray tower
Perforated tray tower
Wetted wall tower
Bubble cap tower
✅ The correct answer is option D.
115. If G = insoluble gas in gas stream and L = non-volatile solvent in liquid stream, then the slope of the operating line for the absorber is
L/G
G/L
Always < 1
None of these
✅ The correct answer is option A.
116. Boiling point diagram is
Not affected by pressure
Affected by pressure
A plot of temperature vs. liquid composition
A plot of temperature vs. vapour composition
✅ The correct answer is option B.
117. Mass transfer co-efficient ‘K’ according to penetration theory varies with mass dif-fusivity as
D0.5
D
1/D
D1.5
✅ The correct answer is option A.
118. Use of packed towers for distillation is generally limited to the
Small sizes
Multicomponent distillation
High pressure operation
Vacuum distillation
✅ The correct answer is option A.
119. Pick out the system with maximum boiling azeotrope at 1 atm.
Acetone chloroform
Ethyl alcohol-water
Benzene-ethyl alcohol
None of these
✅ The correct answer is option A.
120. Mass transfer co-efficient is directly proportional to DAB0.5, according to __________ theory.
Penetration
Surface renewal
Film
None of these
✅ The correct answer is option A.