Diffusion in One Dimension

time

diffusion coefficient D

amplitude concentration

C

0

filling

The equation for unsteady-state diffusion is

∂c

∂t

=D

2

∂

c

∂

2

x

, where

x

is the distance and

c

is the solute concentration. This Demonstration plots the time-evolution of the concentration profile in the solute, for varying coefficient of diffusion and concentration amplitude.The diffusion function

c(x,t)=

c

0

2

πDt

exp

-

2

x

4Dt

is determined as a function of the distance

x

, the diffusion coefficient

D

, and time

t

.