Using your result for D of Cu in Al at 400K estimate the dis

Using your result for D of Cu in Al at 400K, estimate the distance that a Cu impurity would diffuse in Al at 400 K after 1.5 hours. Use the simple estimate x = (Dt)1/2 - Be careful with your units.

Solution

I am taking D as a variable here.

D of Cu in Al is taken at 400K.

Unit of D is mm^2 / sec

Time is 1.5 hours or 3600 secs

Using X = D * t /2

So the Diffusion area is X = D * 1,5 * 3600 /2

X = 2700mm^2