Why does shampoo bubble up?

Answer 1

If you mix water, soap, and air, the soap molecules line up side-by-side to make a layer. One side of this layer has the oily, air-liking ends sticking out and the other side is covered with the water-liking ends. The water molecules stick to the water side and the air to the other side. If you have a lot of air and a little water, which is what happens if you blow a lot of air into a soap-water mixture, then you wind up with a sandwich of three layers: Soap with the oily ends facing the air on either side and water in between. This is just the wall of a soap bubble. So the reason soap, water and air makes bubbles is because air and water molecules don't like to stick together but will stick to different ends of soap molecules.