Does AIR Really Exist?
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Elyse Futterman Bernard Zell Anshe Emet Day School
3760 North Pine Grove
Chicago, IL 60613
Given a teacher demonstration and various learning stations, the students will
learn that air is a real substance which occupies space, exerts pressure, and
The following materials are needed for the teacher demonstration:
2 large soft drink bottles, pencil, balloon, and container with warm water.
The following materials are needed for each station:
1) Piece of paper, balloon, straw, 2 suction-cup plungers, water, 2 8-ounce
plastic tumblers marked A and B, and deep bowl filled with water.
2) Balloon, beaker, test tube, water, ink, plastic bag, twist tie, book, clay,
funnel, jar, straw, and water.
3) Large clear glass jar, plastic bag, string, meter stick, string, pencil
eraser, ring stand, and balloon.
4) Thin board, newspaper, straws, pin, cups, water or juice, ring stand, plastic
tubes, picture of sink and house, air vent, and carpenter's tool.
Teacher demonstration: Set up two large soft drink bottles. Place a pencil
into one, but leave the other bottle empty. Have the students verify that one
bottle is empty. Next attach a small balloon over the top of the empty bottle.
Then set the bottle in a warm container of water (the students should not be
told this). As the students observe, the balloon slowly fills up. The students
will discover that the bottle was not empty!
1. Can I really feel air? Can I see air move?
A. Fan your face with a piece of paper.
B. Blow up a balloon and open the end slowly.
C. Blow through a straw and place your hand near the end of the straw.
D. Moisten the edges of the two plungers. Push the ends of both plungers
together and pull them apart.
E. Look at the glasses marked A and B. Push glass A, mouth first, into the
bowl of water. Turn it on its side. Observe. Push glass B to the bottom
of the bowl, mouth first. Put the mouth of glass A right above glass B and
slowly tip glass B on its side.
2. Does air occupy space?
A. Blow up a balloon.
B. Fill a large beaker half full of water. Add two or three drops of ink to
the water. Insert a test tube open end down. The water does not enter the
test tube because air occupies the space. Tilt the tube so that some air
escapes. Water now enters to occupy the space vacated by the air.
C. Wave about and collect air in a plastic bag. Quickly close the bag and tie
the end with a twist tie. Place the bag on a table top and balance a book
on top of the bag.
D. Mold some clay around the neck of a funnel. Press the funnel into the
mouth of a jug so that an airtight seal is created. Quickly pour water
into the funnel. Observe. Put a straw into your funnel. With your finger
over the upper end of the straw, insert the straw into the neck of the
funnel. Push the straw down through the funnel filled with water. Remove
your finger from the straw. Continue pouring water into the funnel.
3. Does air have weight?
A. A wide glass jar is displayed. Push a plastic bag inside the jar hanging
over the rim. Wrap the string around twice around the rim, just below the
threads, and tie it tightly. Reach inside the jar and pull the plastic
B. Use string to suspend a meter stick in the middle. In one end of a 15-cm
(6-in) length of string, make a loop to fit over the end of the meter
stick. Tie a pencil eraser to the other end of the string. Tie another
loop in a 15-cm. (6-in.) string and tie an empty balloon on the other end
of the meter stick and balance it by moving the eraser on the other end
of the meter stick. Mark where the eraser loop is on the meter stick.
Remove the balloon and inflate it. Retie the balloon in the same place.
4. Does air have pressure?
A. Ask two students to compete in a drink race. See who can drink a small
glass of beverage fastest. See to it that one pupil has a normal straw,
but give the other student a straw filled with pinholes. Have the students
examine the difference.
B. This event should be performed by the teacher. Obtain a thin board. Lay
the board on a table so that one end extends over the edge by 15 to 30 cm.
Place sheets of newspaper over the remainder of the stick on the table. Be
sure to place extra sheets directly over the stick so that the stick does
not cut through the paper when you perform this event. Ask the pupils to
predict what will happen when you push slowly on the stick. Are the
newspapers heavy enough to break the stick? Hit the stick sharply.
C. Plumber's Magic: Set up a model of the p-trap with plastic tubing so that
you design a model of a sink. Have the students pour water into the "sink"
and observe what happens to the water.