1) A beaker with 10 cm in height is filled with liquid solvent n-hexane up to a level 2 cm below the top (mouth) of the beaker at 25°C and 1 bar. With a fan, dry air at 25°C and 1 bar is blown gently across the mouth of the beaker, so that the hexane vapor transferred through the air and n-hexane gas-vapor mixture by diffusion. Hexane concentration at the mouth of the beaker is negligible. Assume that air does not dissolve in liquid hexane, and the liquid height in the beaker is constant within observation period, hence the system is in steady-state. Molecular diffusivity of n-hexane in air is DAB =2x10 m2/s at 25 °C and 1 bar, and vapor pressure of n-hexane is pa°-152 mmHg at 25 °C. a) Draw a schematic picture of the mass transfer in the beaker. b) Discuss the type of mass transfer in the gas-vapor mixture. c) Using the equation dy N=-CDAB + yA + N dz Derive the molar flux equation for the condition given, showing every step of integration.

1) A beaker with 10 cm in height is filled with liquid solvent n-hexane up to a level 2 cm below the top (mouth) of the beaker at 25°C and 1 bar. With a fan, dry air at 25°C and 1 bar is blown gently across the mouth of the beaker, so that the hexane vapor transferred through the air and n-hexane gas-vapor mixture by diffusion. Hexane concentration at the mouth of the beaker is negligible. Assume that air does not dissolve in liquid hexane, and the liquid height in the beaker is constant within observation period, hence the system is in steady-state. Molecular diffusivity of n-hexane in air is DAB =2x10 m2/s at 25 °C and 1 bar, and vapor pressure of n-hexane is pa°-152 mmHg at 25 °C. a) Draw a schematic picture of the mass transfer in the beaker. b) Discuss the type of mass transfer in the gas-vapor mixture. c) Using the equation dy N=-CDAB + yA + N dz Derive the molar flux equation for the condition given, showing every step of integration.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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