How do soap bubbles work?

Soap makes water stretchy, so it holds air. You blow, and a round bubble grows. The shiny skin is thin and wet. A poke makes it pop!

Soap helps water make a thin, stretchy skin. When you blow air into it, the skin wraps around the air and closes into a ball, like a tiny water balloon. The bubble shines because light bounces off its wet skin. It pops when the skin gets too dry, touches something sharp, or is bumped hard.

A soap bubble is a pocket of air wrapped in a very thin film, which means a wet layer. Soap mixes with water and lowers surface tension, the pull that makes plain water shrink together. That lets the film stretch without breaking right away. Bubbles become round because a sphere uses the least film to hold the air inside. Fun fact: the rainbow colors are not from paint. They happen because light bounces from both sides of the thin film and mixes in different ways.