How is diffusion occuring?

Let’s start with what you observe when you actually do the experiment.

Tell us what you see happening. Then we can talk about diffusion, OK?

There were bubbles in the bag. They kept getting larger. Then, the corn starch started getting a light pinkish purple color. It eventually became dark blue in color.

What made the corn starch change colour?

It was outside the bag with the water and cornstarch at the start?

Hint: If you drop iodine into some corn starch mixed with water, what will you see right away?

its turns blue. the iodine diffused inside the bag, but i don’t know how. if you drop iodine in the mixture, it immediately changes color.

The process by which the iodine in beaker got into the bag is called __________?

Osmosis?

Yes, and the process by which the colour spreads throughout the mixture in the bag with starch and water is called _____________?

I don’t know. All i know is that it is a chemical change.

The correct answer to my last question is somewhere in your original question.

Is it diffusion?

Yes it is! Mazel Tov (Congratulations) You understand what is going on. Thank you for your patience.

Thank you, very much. I think I understand.

@achelita You are very welcome. Good luck with your studies.

Nice explanation @Dr_Lawrence. Diffusion is something that happens across some sort of membrane. Try to think here of the iodine diffusing across a plastic membrane, trying to slowly even out it’s concentration on both sides of the membrane.

@cockswain Actually that part is osmosis.
Read the whole thread again for clarification

Osmosis is defined as diffusion across a membrane. Not sure what you’re correcting me on, I read the thread and liked what you said.

Oh wait, I see what you mean, this was an incorrect statement: “Diffusion is something that happens across some sort of membrane.” I should have said osmosis is diffusion across a membrane. Diffusion is a solute trying to reach equal concentration.

@Dr_Lawrence , Nicely done! That is the first example of Socratic method I have seen on Fluther. For it to work well, asker and answerer should be online at the same time.