(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Calculate the flux of oxygen across a square centimeter membrane [2[tex]\mu[/tex], or 2x10 [tex]^{-6}[/tex]m thick if the concentration on the right hand side of the membrane is 4mL/L and on the left side is 2mL/L.

2. Relevant equations

fick's first law of diffusion

Flux = dC/dx = D[C2-C1] where D is the molecular diffusion constant

molecular diffusion constant for oxygen = 3x10^-5

3. The attempt at a solution

Using the first eq, I took the difference in the concentrations, and divided it by the thickness of the membrane. [4mL/L-2mL/L]/ 2[tex]\mu[/tex], which resulted in a flux of 1x10[tex]^{6}[/tex]... however, the equation did not take into account the molecular diffusion constant of oxygen, which was provided in the problem. So then I tried the second equation. 3x10[tex]^{-5}[/tex]x[4mL/L - 2mL/L]= 6x10[tex]^{-5}[/tex]. however, the second equation does not take into account the thickness of the membrane (dx). Im totally lost and have no idea what to do. please help thanks!

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# Homework Help: Molecular diffusion question; fick's first law

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