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At which condition molar flux with respect to a...

At which condition molar flux with respect to a stationary observer and with respect to an observer moving with molar average velocity?

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asked Sep 20, 2022 in Mass Transfer by Julian (39.8k points)

At which condition molar flux with respect to a stationary observer and with respect to an observer moving with molar average velocity?

(a) In a very dilute solution

(b) In a highly concentrated solution

(c) At moderate concentration

(d) Never

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Enquiry is from Fick’s Law-2 in portion Modes and Diffusion of Mass Transfer

mass transfer
modes and diffusion
fick’s law-2

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1 Answer

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answered Oct 11, 2022 by Chris (39.8k points)

The correct answer is (a) In a very dilute solution

Explanation: In a very dilute solution, the contribution of the bulk flow term becomes negligible.

                    NA= (NA+NB)CA/C – DABdCA/dz (general equation)

                    (NA+NB)CA/C =0                             (in dilute solution)

                     NA= -DABdCA/dz = JA.

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