States of Matter in a Baggie

What You Do:

1. Mix a batch of Kool-Aid or Hawaiian punch, or a more nutritious organic juice if you prefer, as long as it's brightly colored. Use it to fill an ice cube tray and leave it in the freezer until you've made solid ice cubes.
2. Once you've made your juice ice, have your child put a few cubes in a resealable baggie, and seal it up tightly.
3. Have your child squeeze the ice cubes in the baggie, and determine what state of matter they currently represent. (They should be in the solid state, because they maintain their shape.)
4. Tape the baggie to an indoor window, where it can get direct sunlight for most of the day.
5. Have your child observe the contents of the baggie about once every half an hour. What can she see happening? Is the ice cube still a solid? Has it become a liquid or a gas? How does she know? (A liquid takes the shape of its container, and flows.)
6. After the ice melts, of course, it will become a liquid. After several hours, however, your child may begin to notice tiny droplets of water forming at the top of the baggie. This is because with the heat of the sun, the water evaporated into the air inside the baggie, and formed water vapor, a gas. Since the vapor cannot escape, it begins to condense on the baggie, forming tiny droplets of water and returning to the liquid phase once again. Ask your child some questions to get her thinking more about states of matter:
7. What causes the water in the baggie to change from one state of matter to another? (The temperature.)
8. What could she do to prevent the water droplets from forming in the baggie? (She could refreeze the water, so it could become a solid again. Or, she could open the baggie to let the water vapor escape. Eventually all the water would evaporate into the air.)
9. Okay, now the most important part: what tastes better - frozen juice, cold liquid juice, or warm liquid juice?