Magic Sand

Sand with a hydrophobic coating...

Clicking a thumbnail on this web page (http://chemistry.beloit.edu/edetc/cineplex/sand/index.html) shows a movie of that demonstration.

Magic sand is poured into a beaker of water. An air bubble separates the magic sand from the water and makes it appear silvery.

Magic sand is sprinkled gently on top of water. Surface tension initially keeps the sand floating on top of the water. When the weight of the sand overcomes surface tension the sand sinks to the bottom

Water is poured out of a beaker containing magic sand. The magic sand remains free flowing and dry.

Water drops are added to magic sand. The hydrophobic nature of the sand makes the water drops highly spherical.

Drops of water added to magic sand and then absorbed by a paper towel.

Equal amounts of water are added to beakers of beach sand and magic sand. All of the water can be recovered from the flask with magic sand. None of the water added to beach sand can be poured back because the water gets absorbed to the surface of the beach sand.

Materials

Magic sand can be purchased from
Steve Spangler Science http://www.stevespanglerscience.com
Educational Innovations http://www.teachersource.com
Flinn Scientific http://www.flinnsci.com/

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