Question

You want to make meatballs according to a recipe that says to marinate the meatballs in garlic and soy sauce before baking them in the oven. You prepare the marinade and immerse the meatballs, which are 6 cm in diameter, in it for 1 hour. When cutting into one of these rather large meatballs, you can clearly see how far the dark colored soy sauce has diffused in the white colored pork. You notice that only the outer 1 cm is marinated.

The question is what is the diffusion coefficient of marinade in these meatballs cm2/sec