Colorful Creations with Candy: Candy is a mixture of substances including sugar, flavoring, and food coloring. Candy is designed to dissolve quickly when it enters your mouth so you can fully enjoy the wonderful taste. As the substances dissolve, they naturally move from a place where they are crowded, or concentrated, to a place where they are less crowded. This process is called diffusion. When candy is placed in water instead of your mouth, the coloring is the first substance that dissolves and then spreads out. This provides a great change to observe the process of diffusion.