Cleaning up - how soap works
Ever wonder how soap cleans your hands? Here is a fun way to learn the process! Materials: hotel sized bar of soap; sugar cube; 2 bowls of water and 12 toothpicks. Process: Place a sugar cube in the center of the bowl of water the arrange 6 toothpicks in a circle around the sugar. In the second bowl place the soap in the center surrounded by toothpicks.
Result: The toothpicks are drawn to the sugar and repelled from the soap. This happens because the sugar sucks up water and creates a current drawing in the toothpicks. The soap releases an oily film that weakens water surface tension and thus these toothpicks flat away from the soap.