A tiny science story

Why does soap wash away grease?

Water can’t grab grease on its own. Soap is the helper that makes it happen — here’s the secret.

Wiggly grease drops meet soap. Each soap’s tail grabs the grease, its head still loves water — so together they roll into a tiny bubble that water happily carries away.
1

Water can’t do it alone

Water sticks to water. Grease sticks to grease. They don’t like each other, so plain water slides right off the grease.

2

Soap plays a trick

Every soap molecule is like a balloon: a round head that loves water, and a tail that loves grease.

3

Grease gets packed up

The tails dive in and grab the grease. The heads point out, still holding water. The grease is now trapped inside a tiny soap-bubble, called a micelle.

Try it: rub a little soap on your greasy fingers, then add water. You’ll see the bubbles form — those are micelles carrying the grease away. The grease isn’t destroyed, it’s just hitchhiking out.
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