I'm curious how to solve Fick's second law of diffusion [tex]\frac{∂c}{∂t}=D \frac{∂^2c}{∂x^2}[/tex]For conditions:[tex]c(x,0)=0[/tex][tex]c(0,t)=A[/tex][tex]c(\infty,t)=0[/tex]Physically this means:(adsbygoogle = window.adsbygoogle || []).push({});

-c(x,t) is the concentration at point x at time t.

-Initially there is no concentration of diffusing species.

-At x=0 for all t the is a constant concentration "a".

-As x goes to infinity for all time, the concentration is 0.

-D is the diffusivity, assume it is a constant.

The solution is:[tex]c(x,t)=A erfc(\frac{x}{2\sqrt{Dt}})[/tex]

What method was used to arrive at that solution?

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# Solve Fick's second law of diffusion

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