Motivation Developing Observational Skills

Sodium polyacrylamide polymer expands as much as 600% by slowly absorbing water. A little powder, cleverly hidden on the bottom of a non see- through cup, will absorb water poured into the cup. When the cup is later inverted the water is "magically" gone!

3 non see-through cups
Sodium polyacrylamide polymer à obtained from Flinn or Educational Innovations
Pitcher or Large beaker to pour water

Set up before hand one cup (the one you will pour water into) with a scoop of sodium polyacrylamide polymer.

Safety

Wear protective gloves, chemical resistant apron and safety goggles

Pour about 1/2 cup of water into cup containing the sodium polyacrylamide polymer. Slowly move cups around so students can easily tell where the water cup is. Ask a student to select a cup NOT containing water. Invert this cup over student's head. Remove cup from game and have another student pick from remaining two cups. Invert over student head. When last remaining student balks at having water cup inverted over his head turn cup upside down over your head. No water comes out!

Sodium polyacrylamide polymer will form a gel on the bottom of the cup. This can be disposed of in a solid waste container.