Mass Transfer Questions And Answers.

1.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

2.Humidification involves mass transfer between a pure liquid phase and a fixed gas, which is__?
A. Insoluble in the liquid
B. Soluble in the liquid
C. Non-ideal in nature
D. At a fixed temperature

3.The mass transfer co-efficient for a solid sphere of radius �a� dissolving in a large volume of quiescent liquid, in which �D� is the diffusivity of solute, is _?
A. D/a
B. D/2a
C. Proportional to ?D
D. Dependent on the Reynolds number

4.Cox chart, which is useful in the design of distillation column particularly for petroleum hydrocarbons, is a plot of (where, P = vapor pressure, T = temperature) ?
A. log P vs. T
B. log P vs. log T
C. T vs. P
D. P vs. log T

5.The commonly used solvent in supercritical extraction is____?
A. Methyl ethyl ketone
B. Water
C. Carbon tetrachloride
D. Carbon dioxide