Vanishing Volume

When 50mL of water are added to 50mL of ethanol in a 100mL graduated cylinder, there are only ~97mL of liquid. Ethanol and water molecules are attracted to each other through hydrogen bonding. The two molecules pack closer together with each other than they do with just themselves.

Rainbow in a Beaker

densities of sugar solutions layering liquids

Sugar solutions that have different concentrations have different densities; the more sugar in a solution the more dense it is. Therefore less dense solutions can be layered on top of denser ones.

Color Tornado

food coloring tornado in water on a hot plate

In this demo, food coloring is added to a stirring beaker of water to create a tornado of color. This could be used as an example of a physical change, or to demonstrate the importance of properly mixing solutions.