School of Physics Lecture Demonstration Manual

He-9 Diffusion

Published: Tuesday 05 June 2007 - Updated: Monday 28 March 2011


To demonstrate diffusion.



Click on pictures to enlarge.

Diffusion pic 1

Diffusion pic 2


A volume of water is heated up to a temperature of 60degrees centigrade and placed into the viewing cell. Four scoops of Potassium Permanganate are dissolved into 30ml of water to create a dark purple coloured solution. The Potassium Permanganate solution is heated to a temperature of 45 degrees centigrade and a small quantity is placed using an eyedropper into the bottom of the 60degree volume of water. This should create two distinct layers of solution with the purple Potassium Permanganate solution settling on the bottom. The Potassium Permanganate will slowly diffuse into the volume of water. The process may take a couple of hours to be completed. The process will begin immediately.

Safety notes

Chemical Safety 


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