What travels in Air?
Time: 10 min -- 2 days Best location: indoors Materials:
- clean glass bottles or jar
- steel wool
- soup bowl
- 2 glass custard cups
- lime water
- tin can
- ice cubes
Two of the following 5 activities will require 24-48 hours to complete; the others can be done in 10-15 minutes.
The teacher/leader should demonstrate these activities to the children. Following the activities the teacher can stress impacts of these things on t he environment, people, animals and plants, both good and bad.
- Air contains OXYGEN. Push a wad of steel wool down to the bottom of a bottle. Fill the bottle about half full of water and shake it well, until the steel wool is very wet. Pour out the water. Put one inch of water in a soup bowl. Now put the bottle, mouth down, into the bowl and leave it for 24 hours. The water will rise up into the bottle. The steel wool will become rusty. The steel wool, combined with oxygen in the air inside the bottle, formed rust. The water then rose to take the place of the oxygen in the air that was used up by the steel wool.
- Air contains CARBON DIOXIDE. Put a small amount of lime water into two clear custard cups. Using a straw, blow into the lime water in one cup. The carbon dioxide from ;your breath will make the lime water milky. Place a second cup of lime water in the fresh air for a few hours. Watch what happens. Whenever carbon dioxide meets lime water, the lime water becomes milky.
- Air contains WATER VAPOR. Get a tin can which has had the top smoothly remove. Remove the label and scrub the can with steel wool until it is bright and shiny. Fill it half full of cold water. Add two or three ice cubes. Soon, droplets of water will from on the sides of the can. When water vapor in the air changes back into droplets of water.
- Air contains DUST. Pull down the shades in a room, switch off the lights, and turn on a flashlight. Little specks of dust will be dancing in the beam of light. (You can often observe dust particles in a ray of sunlight coming through a window.)
- Air contains SMOKE AND SOOT. Cut out a piece of white paper so that it fits the bottom of a deep cake pan. Place the paper in the cake pan, and put a rock on the paper to keep it down. Put the pan outside on a windowsill so that outside air can reach it. After a day or two, see how much smoke and soot has collected.