Soap bubbles

Whether you are a small kid or an adult, I am sure all of us enjoy playing with bubbles. The joy of chasing  the bubbles,  to catch it before it bursts is immense. Don't you agree with me? . So, that is what we did this week learning about bubbles. We had loads of fun.


First, we discussed about bubbles related to the science behind
1. what is a bubble?
2. How the molecules are arranged to hold its shape?
3. How to keep them for long?.






A soap bubble is an extremely thin film of soapy water enclosing air that forms a hollow sphere.

To understand how soap bubbles are holding the shape when water is mixed with soap we need to know that soap molecule has a hydrophilic head and a hydrophobic tail. The diagram  shows the arrangement of molecules in a bubble.




We also did the same with spoons and bottle caps. White spoons (spoon head- hydrophilic and spoon handle - hydrophobic) are the soap molecules and bottle caps are the water trapped in between them. When the water evaporates then the bubble breaks.


We  mixed oil and water in a bottle. The oil and water molecules did not mix up , but remained as separate layers.



But once the soap is added it mixes to remove the oil. Hydrophilic part of the soap mixes with water and the hydrophobic part of it mixes with oil and makes it easier to remove..

Kids made their own bubble solution. Recipe follows:

Materials needed

6 spoons - dishwashing liquid
24 spoons - water
1 tsp - glycerin
We made bubbles, but they were breaking off, so to have bigger bubbles that doesn't break faster we added glycerin. Basically glycerin doesn't allow the water to evaporate.

We checked to see if a square, triangle shape would make square, triangle shape bubbles.  . Unfortunately it was only spherical. We discussed about the reason. Shreya, rightfully pointed out that it was because it can elongate to become bigger with out breaking.



 Yes.... sphere takes a lesser surface area, but has bigger volume.