A Hole in the Water

This is a very cool demonstration!  Make sure you only use a spoonful or two of water - I tried to do this repeatedly, but with too much water, and was getting very frustrated by the lack of results.  When I broke down and followed the directions, it worked beautifully.  I had to do it 3 times in a row just to marvel at it!  

Place a spoonful of water onto a plate.  Add a drop of food coloring and swirl to mix.

When the water has settled, add a few drops of rubbing alcohol to the center of the water.

Watch the water pull away from the alcohol - the alcohol has less surface tension than the water.  The water molecules want to stick together (literally), so they pull away from the alcohol, leaving a hole in the middle.

Watch the edge of the water.  It literally quivers as it tries to stick together.  So cool!