National Chemistry Week - Experiments - Amazing Powder

THE AIM:

To demonstrate the amazing effect that a powder from diapers has on water.

WHAT YOU WILL NEED:

• 4 thin-style diapers
• scissors
• piece of paper
• 1 drinking glass
• water
• salt
• spoon for stirring

WHAT TO DO:

1. Cut open each diaper on the inside using a pair of scissors.
2. Remove the cottony stuffing and pull it apart over a piece of paper to collect the powder from inside the diaper. Pour this powder into a glass.
3. There should be about 5 mL (1 teaspoon) of powder at the bottom of the glass.
4. Place 45 mL (3 tablespoons) of water in the glass over the powder.
5. Swirl the water around slightly.
6. Make observations.

The water turns to a gel when it is mixed with even a small amount of this powder. This amazing powder makes water stick together quite well! This is why the diaper can be made so thin, yet absorbent.

To make the effect even more dramatic, the gel can be turned back into a liquid if table salt is added. Pour about 5 mL (1 teaspoon) of salt into the glass and stir the mixture. Notice what happens to the gel. Salt breaks apart the gel after a short time.