How does soap help remove germs more than just plain water does?
By chemical reactions of course...
Soap is made up of oils, which have a hydrophobic head and a hydrophilic head. Both parts play an important role in helping to remove germs. The hydrophobic head dissolves the cell membrane of the bacteria/germs, while the hydrophilic head attracts the water molecules together, so it can easily be washed away.
That's a short introduction on how some soaps work.
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