Background

Diffusion is the movement of particles from a place of high concentration to a place of low concentration. We can also say that particles move from where there are lots of particles to where there are less particles.

In this experiment we are going to look at the diffusion of colour particles. You will observe the colour moving away from the sweets where lots of colour particles are found to places with less colour particles in the middle of the plate.

You will need

• M&Ms or Smarties
• Plate
• Water

What to do

1. Once you start this experiment, you cannot move it. So, make sure you choose a good spot to start.
2. Pour the bag of M&Ms or Smarties onto your plate.
3. Remove the sweets that landed in the middle of your plate.
4. Place the remaining sweets in a circle around the outside of your plate.
5. Remove any remaining M&Ms or Smarties that do not fit in the circle.
6. Slowly add water to your plate. It needs to reach the M&Ms, but they should not float. From now on you cannot move the experiment.
7. Observe what happens to the colour of the sweets.

You can also watch this experiment on YouTube: