Science
How does soap clean?
Soap cleans because each soap molecule has two ends: one that loves water and one that grabs grease. The grease-loving ends latch onto oils and dirt, while the water-loving ends let water rinse the whole bundle away — lifting grime off your skin.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how soap works.
Step by step
- 1Soap molecules have a water-loving and a grease-loving end.
- 2The grease-loving ends grab oils and dirt.
- 3They surround grime into tiny droplets.
- 4Water then rinses those droplets away.
Frequently asked questions
- How does soap clean?
- Its molecules grab grease at one end and water at the other, so water can rinse trapped dirt away.
- Why doesn't water alone remove grease?
- Grease repels water, so it won't rinse off — soap bridges the two so water can carry grease away.
- How does soap kill germs?
- It breaks apart the fatty outer layer of many microbes and lifts them off so they wash away.