Book 6, Question 6
Why Does Foam Show Up on Waves?
When a wave breaks, it mixes air into the water. Tiny bubbles form, and bits from living things in the sea help them stick together. Piled up, they make foam.
From the book
Page from A Million Whys Book 6
More fun facts
- Sea foam forms when wind and waves mix seawater and trap air bubbles.
- Molecules called surfactants wrap around the air bubbles so they do not pop right away.
- It works like foam on a warm milky drink, where proteins and fats in the milk trap air.
- Proteins, fats, air and water are the main ingredients of foam.
- Foam looks white because light scatters where the water meets the bubbles.
Sources: NOAA, NOAA, NOAA Ocean Service, NASA
Questions kids ask
What is a surfactant?
A substance, like the proteins and fats in milk, that traps air bubbles and helps foam form.