Answer:
1. The soap molecule is made up of two different ends that include polar head which is hydrophilic carrying carboxylate group (-CO2) (binds with water) and the other is non-polar hydrocarbon tail that is hydrophobic carrying hydrocarbon chain (binds with stain) .
When soap water is added with stain or oil, soap molecules form micelles which are the tiny clusters of soap molecules representing hydrophilic head (water-loving) points outwards that sticks to the water and hydrophobic tail (oil-loving) points inwards that stick to the oil and trap oil in the center.
As micelle is soluble in water, the trapped oil or stain is rinsed away along with soapy water.
2. A micelle is defined as a cluster of surfactant molecules that are dispersed water and form a colloidal solution.
3. Emulsification is the process in which soap act as an emulsifier that allows dispersion of immiscible liquid. It means soap will disperse stain or dirt in such a way that it can be removed.
4. As we discussed earlier, Soap has hydrophilic (water-loving) carboxylate group (-CO2) that form hydrogen bonds and ion-dipole interactions with water and the hydrophobic (water-fearing) tail carry nonpolar hydrocarbon chain that interacts with a stain by forming micelles through dispersion force.
The negatively charged carboxylate group (hydrophilic) repels each other and hydrocarbon chain (hydrophobic) trap stain inside and remove the dirt along with water.