Mass Transfer MCQ Questions & Answers | Chemical Engineering Page-4 section-3

Section 1 Section 2 Section 3 Section 4 Section 5 Section 6 Section 7

31.
At 750°K and 1 atm, the approximate value of Schmidt number for air is

A. 0.01

B. 0.1

C. 1

D. 10

Answer & Solution Discuss in Board Save for Later

32.
The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives

A. Low pressure drop and high hold up

B. High pressure drop and low hold up

C. Low pressure drop and low hold up

D. High pressure drop and high hold up

Answer & Solution Discuss in Board Save for Later

33.
During constant rate drying period, vaporisation rate per unit drying surface area

A. Decreases with time

B. Increases with time

C. Does not change with time

D. Does not affect the moisture content of the wet solid

Answer & Solution Discuss in Board Save for Later

34.
During the constant rate period of drying of a solid,

A. Increased air humidity decreases the rate of drying

B. Increasing the air temperature decreases the drying rate

C. Surface evaporation of unbound moisture occurs

D. None of these

Answer & Solution Discuss in Board Save for Later

35.
Inside the distillation column, the

A. Driving force for the vapour flow is the pressure drop

B. Liquids are not always at their bubble points

C. Pressure increases gradually from bottom to the top of the column

D. None of these

Answer & Solution Discuss in Board Save for Later

36.
Pick out the wrong statement.

A. Critical moisture content is not a property of the material itself

B. A sharp increase in pressure drop gives an indication of the flooding in a distillation column

C. Separation of components is not possible in liquid extraction, if selectivity is unity

D. Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum

Answer & Solution Discuss in Board Save for Later

37.
Plate efficiency in a distillation column is reduced due to the __________ of liquid.

A. Entrainment

B. Foaming

C. Weeping & dumping

D. All of the above

Answer & Solution Discuss in Board Save for Later

38.
With increase in temperature, the rate of leaching increases, because the

A. Diffusivity of solute increases

B. Viscosity of solvent decreases

C. Thermal conductivity of solute increases

D. None of these

Answer & Solution Discuss in Board Save for Later

39.
Stage efficiency in a leaching process depends on the

A. Time of contact between the solid and the solution

B. Rate of diffusion of the solute through the solid and into the liquid

C. Both A & B

D. Vapour pressure of the solution

Answer & Solution Discuss in Board Save for Later

40.
In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:
(i) Reflux stream is completely liquid and is at its bubble point.
(ii) Reflux stream is below its bubble point.

A. Condenser and reboiler loads are the same in both the cases

B. Reboiler load is the same in both the cases but condenser load is higher in case (ii)

C. Condenser load is the same in both the cases but reboiler load is higher in case (ii)

D. Both condensor and reboiler loads are higher in case (ii) as compared to case (i)

Answer & Solution Discuss in Board Save for Later

1 2 3 4 5 6 7 8 9 10

Mass Transfer MCQ Questions & Answers | Chemical Engineering

31. At 750°K and 1 atm, the approximate value of Schmidt number for air is

Answer & Solution

32. The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives

Answer & Solution

33. During constant rate drying period, vaporisation rate per unit drying surface area

Answer & Solution

34. During the constant rate period of drying of a solid,

Answer & Solution

35. Inside the distillation column, the

Answer & Solution

36. Pick out the wrong statement.

Answer & Solution

37. Plate efficiency in a distillation column is reduced due to the __________ of liquid.

Answer & Solution

38. With increase in temperature, the rate of leaching increases, because the

Answer & Solution

39. Stage efficiency in a leaching process depends on the

Answer & Solution

40. In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:(i) Reflux stream is completely liquid and is at its bubble point.(ii) Reflux stream is below its bubble point.

Answer & Solution

Read More Section(Mass Transfer)

31.
At 750°K and 1 atm, the approximate value of Schmidt number for air is

32.
The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives

33.
During constant rate drying period, vaporisation rate per unit drying surface area

34.
During the constant rate period of drying of a solid,

35.
Inside the distillation column, the

36.
Pick out the wrong statement.

37.
Plate efficiency in a distillation column is reduced due to the __________ of liquid.

38.
With increase in temperature, the rate of leaching increases, because the

39.
Stage efficiency in a leaching process depends on the

40.
In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:
(i) Reflux stream is completely liquid and is at its bubble point.
(ii) Reflux stream is below its bubble point.