National Chemistry Week - Experiments


National Chemistry Week - Experiments - The Paper Bag Mystery

The Aim:

to find out what is hidden inside an inflated paper lunch bag

What you will need:

6 brown paper lunch bags
marble
penny
pen cap
cotton ball
paper clip
wrapped bouillon cube
(The above items may be replaced by items of similar size.)

What to do:

Insert one item into each paper bag. Label the bags with numbers and keep a list so that you know what is inside them. Make sure that your students do not know what you have put into each paper bag.
Put some air into each bag so that it does not lie flat and then close it with tape. List the objects that are in the bags on the blackboard.
This experiment can be set up in stations where the students can each take a turn at touching and moving the paper bags in an attempt to figure out which object is inside. The students should keep their own lists so that answers may be compared later when the contents are revealed.

[IMAGE OF MOLECULE MAN] [IMAGE OF PAPER BAG WITH HOLE IN IT]

This exercise is very similar to what scientists do to find out what is inside an atom. They cannot see directly inside the atom but can figure it out by other observations.

For an explanation and demonstration of atoms see Atoms and Molecules.

To make this more challenging for upper grades, do not tell the children what the objects are - let them guess.