MathBench > Cellular Processes

Diffusion through a Membrane

And what you've all been waiting for

Here's another kind of possible problem: Using the equation governing the flow of sugar across a membrane from the following equation

And given that

P= 0.02 cm/sec

the area of the membrane between the two solutions is 2 cm2

Solution left side of the membrane = 0.4M

Solution right side of the membrane = 0.1M

What is the rate of diffusion across the membrane for the following concentrations? This kind of problem requires straightforward plug-and-chugging...

0.02cm/sec x 2 cm2 x (0.4M sugar - 0.1M sugar)

= 0.012 moles/second

What would happen if we doubled the permeability constant?

What if we doubled the area of the membrane?

What if we doubled the concentration on the left?