DAD: Why does the soap grab the dirt?
DAD: Because soap is a surfactant.
DAD: Why is soap a surfactant?
DAD: That is an EXCELLENT question. Soap is a surfactant because it forms water-soluble micelles that trap the otherwise insoluble dirt and oil particles.
DAD: Why does soap form micelles?
DAD: Soap molecules are long chains with a polar, hydrophilic head and a non-polar, hydrophobic tail. Can you say ‘hydrophilic’?
and so it goes on...