Why does soap clean?
Show answer & explanation
Answer: Breaks down oils with molecules
Kills all germs instantly — Wrong. Soap removes germs mechanically but doesn't kill them—antibacterial soaps have added chemicals. Soap's cleaning comes from molecular structure.
Breaks down oils with molecules ✓ — Correct! Soap molecules are amphipathic: hydrophilic (water-loving) head and hydrophobic (water-fearing) tail. Tails attach to oils/grease, heads stay in water. This forms micelles—balls with oil trapped inside, hydrophilic outsides. Water rinses micelles away. Emulsification! Surfactants reduce water surface tension. Mechanical scrubbing helps break dirt particles. Soap doesn't kill germs—it removes them!
Heats dirt off surfaces — Wrong. Soap doesn't heat anything. It works through molecular structure—amphipathic molecules bridge water and oil, lifting dirt away.