How to show diffusion?

Question

I'm doing a bio project and i need a way to show diffusion.
I already know about the perfume experiment but i want something different. I have to be able to do it infront of the class for about 5-10 minutes. Please help?

Answer 1

Add a drop of food coloring in water. It starts concentrated and defuses through the water.

Answer 2

Look into Brownian motion, it is responsible for diffusion. That was Einstein's famouse papers in 1905. As for the presentation maybe microscopic cells have to be seen in order to prove. Now I know that in the anatomy of living things there is also diffusion taking place I sometimes get it confused with osmotic pressure differential, but you can check out the small intestine and the diffusion of nutrients into the body. This is another idea.

Answer 3

Diffusion is the movement of molecules from a high conc to a low conc

The guy who said using a food dye is correct, i dont know if this is the best method however.

The one i was shown was 2 glass cylindrical flasks divided by a glass plate.

One glass cylindrical flask contans a brown gas, ( I think it was Br2-should be avaiable in school)

The second flask contans a clear gas-Air ie normal atmospheric mixture)

if you separate these 2 gases they remain as they are but if you remove the glass plate.(do not shake or mix the gases ie try to keep flasks still) the gases should over a period of time dilute and mix until a lighter ahade of brown is reached

This is because of movement of a high conc of Br to a low conc

****NOTE**** but also a movement of air (natural gases) from a high conc to a low conc



hope this helps

Answer 4

you could try putting a tea bag in a pot of cold water vs. a pot of boiling water. You'll see the difference heat makes in diffusion if you try that. Just an idea!

Answer 5

put some drops of ink in water.slowly and slowly the ink will diffuse in the water.