- 1 large-mouthed, clear glass quart jar
- red food coloring
- small baby food jar
- 6-inch square of foil
- rubber band
- 1 ice cube
- 1) Place the ice cube in the baby food jar. Fill the
jar with cold water.
- 2) Fill quart jar within an inch of the top with hot
- 3) Remove ice from baby food jar. Stir in 6-7 drops
of food coloring.
- 4) Cover the mouth of the baby food jar with foil;
use the rubber band to secure the foil.
- 5) Use the point of the pencil to poke a small hole
in the foil.
- 6) Quickly turn the baby food jar up-side down and
hold it so that the hole is just under the hot water.
- 7) Slowly and gently tap the bottom of the baby food
jar with pencil eraser or finger.
Explanation: The taps make the
cold water flow out in smoke-like rings. Because warm water is less dense than
cold water, the rings sink to the bottom.
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