How does soap get things clean?
Dry dirt can be shaken or brushed away. The stubborn dirt on grubby clothes and grimy fingers is stuck there with traces of greasy oil. This is the dirt which seems to dissolve and disappear in soapy water. The soap, of course, is made of molecules, and the magic trick is done by these long and stringy soap molecules. One end of a soap molecule happens to be attracted to water, the other end is attracted to oil. The oil loving end of the molecule grabs the greasy oil and with it goes the grubby dirt. The other end of the soap molecule pulls the oil and dirt toward the water. We could not remove this dirt with soapless water. So, lather up and 1et the little soap molecules pull out the greasy dirt and lose it in the water.
The soap forms molecules that have hydrophilic heads (like water) and hydrophobic (don’t like water) tails. These form a mycelle (think bubble only microscopic) which is 2 back to back. The water goes in because of hydrophillic attraction and then leaves because of hydrophobic repulsion, but the dirt, brought in with the water, can’t penetrate the heads to get back out because the tails don’t mind dirt. Hope that helps.
