eli5 how are soaps able to clean away germs when washing things?


Hello everyone. I have always wanted to know how exactly are dishwashing soap, hand soap, cleaning soap are able to kill or remove harmful bacteria from whatever we are using it for?

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Your skin naturally secretes oils, and the germs on your hands stick to these oils. When you wash your hands with soap, the soap breaks down the oils so they are easily washed away, taking the germs with them.

I believe they change the chemistry of the area they are used in which kills the germs. They also create bubbles that carry them (amongst other things like dead skin or other matter) away in suspension when washed off.
Washing your hands frequently is helpful, but not as effective as using soap, too.

Picture soap as a chain, one half sticks to oils and dirt, other half sticks to water and takes the oils and dirt away with it when u rinse.

When you wash something we’ll say your hands, the soap and the friction that comes from lathering and scrubbing your hands helps lift dirt, grease and other grossness off them, then you rinse away everything you just scrapped off…done deal

Soap is actually really cool! Essentially one end of the molecule attracts water (hydrophilic) and the other side repels water (hydrophobic). The hydrophobic end will bind to oil or bacteria and the hydrophilic end to water, which allows the water to pull these things away from your hands.

Many bacteria and viruses have an outer membrane that’s made mostly of oil molecules (lipids).

Soap in hot water breaks up oils and carries them away.

Not only does this help remove the germs from surfaces, it also causes some of the germs to just pop and die; all their insides come out and are washed away.

I’m gonna do an ELI10 because understanding this base concept is pretty useful.

In general, there are two kinds of molecules. Polar and non polar. Polar molecules have the electrical charges unbalanced across them, which makes them like little magnets. Non polar molecules do not have this charge imbalance. Good examples are water and oil, with water being polar and oil being non polar.

Each type of molecule loves sticking to itself, but *hates* sticking to the other. This is actually the half of the “oil doesn’t mix with water” thing. Not only is the oil less dense than water, but they refuse to intermingle because they aren’t the same type of molecule.

This presents a problem, though. Water is great at cleaning polar stuff off of things, but what about non polar stuff? That’s where soap comes in. Soap is really weird. One end of the soap is polar, but the other end is non polar. So it can stick to both types of molecule. What soap will do in water is go around and make tiny little corrals around all the non polar stuff, completely surrounding it in microscopic coating. The inside of the corral is non-polar and sticks to the debris, but the outside is polar. This means that water can grab the entire corral like it’s one massive molecule and sweep it away.

soap shreds germs.