Activity

Bubbles - make bubble mix and bubble blowers

Summary
Students make their own bubble mix from shampoo and water, and their own bubble blowers from straws and pipecleaners.
Science content
Chemistry: States of Matter, Properties of Materials (K-7)
Chemistry: Physical Changes, Solutions, Mixtures and Separating (2, 4, 5, 6)
Lessons activity is in
Materials
  • Tube for each student (e.g. 50 ml Falcon tube) containing 10ml Johnson's Baby Shampoo
  • Water, 10ml per student, in a small cup easy to pour
  • Coffee stirrer per student
  • Straw per student
  • Pipecleaner per student
Procedure

Who’s blown bubbles before? We’ll make our own bubble mix today, then you can see what the basic ingredients are. This is the recipe that science world uses.
Smell the tube. What is in it? Baby shampoo. It’s soap. Soap makes bubbles.
We’ll add the same amount of water. What number do we add water to?
Mix it with the stick, then put the lid on, and gently invert to mix. Do not shake.

Now we have our bubble mix.
The simplest bubble blower is a straw.
Students dip their straw in bubble mix, take it out, and blow bubbles (they will generally be quite small).
Challenge: How can you make lots of small bubbles, or one large bubble. Control how you breathe.
While you are blowing, figure out what each bubble actually is. (Air inside a layer of soap.)
The soap molecules can move around within their layer, to settle at the most stable shape: a sphere.
If you make many small air bubbles that pile up, you make a foam (a kind of colloid mixture that is bubbles of gas trapped in a liquid (the soap mix)).

Look at the commercial bubble blower. What is the difference between theirs and ours that might make more bubbles? It has more places for the bubble mix to sit - so can make bigger bubbles.
Try making a pipecleaner blower, which should hold more mix: make a loop at the end of a pipcleaner. (Optional: push the straw on the long end for a handle.)
You should be able to make more and/or bigger bubbles because the pipecleaner fuzz holds more bubble mix.

Notes

In the DI Science workshop - they just made their own blowers, and used previously made bubble mix.
For winter 2011 science club (grades 1 and 2) we did this inside. Students sat around the perimeter of a large blanket and blew their bubbles into the centre of the blanket.

Detergent in baby shampoo is Cocamidopropyl betaine, which is mostly CH3(CH2)10C(O)N(H)CH2CH2CH2N+(CH3)2CH2CO2-

Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5