Just happen to see a video on colour change of the KMnO4. So I decided to try it out as the chemical needed is quite easy available.
You may have seen alot of people mixing sucrose, sodium hydroxide and potassium permanganate in youtube. This reaction occurs because the Manganese is being reduce from 7+ to 3+.
Therefore for every reduction of the manganese the state of colour is different which is why we can see the colour changes from purple (7+) to grey/blue (6+) to green (5+) to yellow (4+) and finally to orange (3+). Orange is a bit difficult to differentiate from yellow from my video. So in my video I just wrote the final colour is yellow.
Have a look at my video, it can be found in youtube too. http://www.youtube.com/watch?v=_9FQlxDu28U
