There is a lot of dirt and contaminants mixed with water, and most of all the impurities do not dissolve in the water. Soap molecules are a mixture of salts such as sodium or potassium.

Molecules contain a long series of carboxylic acids. Therefore, when the carbon chain dissolves in the oil and the ionic ends dissolve in the water, the soap begins to clean and absorb the impurities.

When this happens, soap molecules form structures called micelles that are used to trap oil droplets and eventually to ionic surface.

This will then form an emulsion in the water and help eliminate dirt or grime when the clothes are washed.