The Chemistry of Bigger Bubbles

Yvonne Tuck                    Ericson Academy
                               3600 West 5th Avenue
                               Chicago IL 60624
                               312-535-6660

Objectives:

1. Compare the size of bubbles
2. Compare shapes and colors of bubbles
3. Learn about surface tension
4. Learn that water evaporates very rapidly
5. Learn that all liquids form bubbles but their life span is short
6. Learn that soap breaks the surface tension

Materials needed per class:
                                                         
Bubble solution - 1 cup dishwashing liquid, 1 gallon of water, 1/4 cup glycerin
Bubble solution must be made at least eight hours before using and should be 
refrigerated. 

Soda straws, glycerin, powder jello, karo syrup, paper clips measuring cup, 
large pans, plastic trays calculators, meter sticks, eyedroppers, milk, cream, 
distilled water, orange soda in a bottle, and tap water, paper towels, mop, news 
paper, dry ice, clear quart containers, aquarium
                   
Strategy:

This activity will be used with forth graders, but can be up graded to a higher 
level.  This activity will introduce students to some of the properties of 
bubble making substances.  The student will observe how soap affects the surface 
tension of water.  Give each student an eyedropper and a penny.  Ask them to 
predict how many drops of water will fit on the penny without spilling.  
Distribute dishes of water and have the student find out if the water will spill 
off the penny.  After the students have a chance to observe the surface tension 
of the water on a penny, ask them to put drops of water on a penny again, then 
break the surface tension of the water on the penny by adding a drop of soap 
solution. 

This activity presents a plan for varying the amount of glycerin while keeping 
the amount of water and dishwashing liquid the same.
Formula one = 0 drops
Formula two = 10 drops
Formula three = 20 drops
Formula four = 30 drops
Formula five = 40 drops 
Formula six = 50 drops
Formula seven = 60 drops
Formula eight = 70 drops
Ask the student if they have any expectations about the experiments.  How much 
glycerin will make the largest bubble?

The student will be given 12 soda straws and 24 paperclips to construct the 
geometric figure of a cube.  This will be used to create the square bubble. 
Connect all of the straws with the paperclips.  After the cube is assembled, dip 
the cube into formula 8 above.  All sides must be submerged, the room must be 
free from drafts and the temperature must be about 70oF in order to be 
successful in bubble making. 

The next experiment demonstrates that soap bubbles will float on a cushion of 
carbon dioxide.  Place some dry ice flat on the bottom of an aquarium.  Allow a 
few minutes for a layer of carbon dioxide gas to accumulate.  Blow bubbles so 
that they float down into the aquarium.  The bubbles will descend and then 
float over the denser layer of carbon dioxide gas.  These are the things to 
observe.  Bubbles will freeze on the dry ice.  The bubbles will have various 
color bands.  The bubbles will float.  The bubbles will dance.   

Performance Assessment:

Budapest Bob, the bubble archaeologist is trying to find the giant rainbow 
bubble that contains the map to a treasure.  In order to achieve this task, you 
must help him to find the map by going through a maze and completing each task.  

These are the obstacles that he will encounter on the way:

1. What substance does he use to make the largest bubble in order to get him 
over the dangerous animals?

2. What substance does he need for the strongest bubble in order to escape the 
dragonfly?

A wizard blocks the path of Budapest Bob.  In order to pass, he must answer the 
following questions:

A. How many colors will be seen in a bubble?
B. What order are the colors?
C. When handed several types of milk, what milk should he use for the strongest 
bubbles?

He now is near the end.  He sees the large rainbow pointing toward the giant 
square bubble.  He also encounters a robot that is blocking the path that will 
lead him to the treasure.  You create a square bubble that will help Budapest 
Bob escape to safety.  

You have arrived successfully at your treasure!