Bubble-ology

Shelia Buchanan
Cynthia Daniels
Brenda Pieper

TITLE OF THE LESSON: Activity 5 - Predict-a-Pop

TECHNOLOGY LESSON: No

DATE OF LESSON: Monday, Tuesday, and Wednesday of week 3

LENGTH OF LESSON: 3 sessions 45 minutes long each

NAME OF COURSE: 6^th Grade Science

SOURCE OF THE LESSON: Bubble-ology, Activity 5, Pages: 35-40, Great Exploration in Math and Science (GEMS)

TEKS ADDRESSED:
§112.22. Science, Grade 6.

(b)  Knowledge and skills.

(2)  Scientific processes. The student uses scientific inquiry methods during field and laboratory investigations. The student is expected to:

(B)  collect data by observing and measuring;

(C)  analyze and interpret information to construct reasonable explanations from direct and indirect evidence;

(D)  communicate valid conclusions

CONCEPT STATEMENT:

POP! GOES THE BUBBLE

Surface tension is what makes bubbles possible. So what happens when you break that surface tension of a bubble? A hole has broken the bubble wall and the bubble popped!The evaporation of water and gravity will also cause a hole in the bubble wall.

If you look closely at a soap bubble, you will see lots of shimmering colors.Just like a prism, soap film causes white light to separate into its component colors.A rainbow is created in a similar way when water droplets in the air break up sunlight passing through them.

Color, one of the most beautiful aspects of bubbles, provides us with an accurate tool for measuring the thickness of the soap film and predicting the pop of a bubble.Light waves have peaks and valleys (crests and troughs). Red light has the longest wavelength and violet the shortest.   We see the colors in a bubble through the reflection and the refraction of light waves off the inner and outer surfaces of the bubble wall. A bubble reflects color from its surroundings. When a light wave hits the surface of a bubble, part of the light is reflected back to your eye from the outer surface.  The other part of the light is reflected from the inner surface.  As the two waves of light travel back, they interfere with one another causing what we know as color.  When the waves reinforce each other, the color is intense.  This is called constructive interference.When the wave gets close to canceling each other out, there is almost no color or darkness.This is called destructive interference.   As a bubble wall gets thinner the distance between the inner surface and the outer surface of the bubble becomes less and less until the two reflected waves of light start to coincide and cancel each other out.  The result is that the bubble loses its color and can become nearly invisible.
  
     There are many reasons why a bubble pops. Evaporation of its water content, air, and dryness - contact with a dry surface or dry air. When you make bubbles in the sun, they evaporate quickly. When there is a strong wind, or even a gentle breeze, bubbles are much more difficult to create and are popped by the wind's force. If the air is very dry or if a bubble touches a dry finger or a piece of clothing it pops instantly.

http://www.bubbles.org/html/questions/questions.htm

PERFORMANCE OBJECTIVES:

• record the color changes of a bubble.
• use color changes to accrurately predict when a bubble will POP.
  describe why  bubbles change colors.

RESOURCES:

Soap mixture:

            1 cup dishwashing liquid

            1 gallon water

            50-60 drops of glycerin

Each pair or group of students

            1 pint-sized container for solution

            2 plastic straws

            6 8½X11 sheets of paper

            1 flat, dark surface or cafeteria tray with black construction paper

            Tape

SAFETY CONSIDERATIONS:

Straws must not be shared.Inform students to throw straws away after they are done with the experiment to prevent the sharing of germs.If soap gets into a student's eye, immediately inform the teacher.

SUPPLEMENTARY MATERIALS, HANDOUTS:

No supplementary materials and or handouts for this particular activity.