When a crystal of potassium permanganate is placed in a beaker, its purple colour spreads throughout the water. What does this observation tell us about the nature of potassium permanganate and water?

When we place potassium permanganate crystals into the water, it's purple colour spreads throughout the water. This shows the diffusion of potassium permanganate in the water. Potassium permanganate has tiny particles, which get into the space between the water molecules. That's how its purple colour spreads throughout the water.