Fick’s Law of Diffusion

Fick's law states that the rate of diffusion of a substance across unit area (such as a surface or membrane) is proportional to the concentration gradient.

Formula

  • W = (DA) \( (Co-Ce)t \over L \)
Variable Unit
W nanograms
DA D =Diffusion coefficient (cm2/min); A = Cross-sectional area of the diffusion path (cm2)
Co mg/m3
Ce mg/m3
t minute
L centimeters

Fick’s Law of Diffusion

W = (DA) \( (Co-Ce)t \over L \)
W
= (
DA
)
(
Co
-
Ce
) *
T
 /
L

Digits of Precision:

mg/m3
mg/m3
min
cm