Explore topic-wise MCQs in Mass Transfer.

This section includes 2 Mcqs, each offering curated multiple-choice questions to sharpen your Mass Transfer knowledge and support exam preparation. Choose a topic below to get started.

1.

In an accident a container containing ethanol(s.g 0.789) falls down in a room of dimension 1*1*2(all in m). Ethanol forms a layer of 2mm. Ethanol vaporizes and diffuses through a stagnant film of air of thickness 2.5mm. What will be the time required for the water layer to disappear completely. The diffusivity of ethanol in air is 2.567*10-5 m2/s. the total pressure is 1.013 bar and the pressure of ethanol in bulk air is 0.02244 bar and at the ethanol-air interface is 0.02718bar. The temperature is 25.2 C.

A. 4.73h
B. 14.6h
C. 5.87h
D. 16.2h
Answer» B. 14.6h
Discussion
2.

Oxygen diffuses through a stagnant layer of air, 1mm thick, ambient temperature 28 C and 1atm total pressure. The partial pressure of oxygen on two sides of layer is P1=0.9atm and P2=0.1atm respectively. Calculate the value of Molar flux (in mol/m2.s) with respect to an observer moving with molar average velocity. Calculate this value at the end of the path where P2=0.1atm. Use R=8.205*10-5m3atmK-1mol-1.

A. 2.713
B. 1.713
C. 0.1713
D. 0.01713
Answer» C. 0.1713
Discussion