Soap

Soap is a salt of fatty acid. (a base + fatty acid)

• It is composed of countless amphiphilic compounds, which contain a water loving (polar) head and a water hating (non-polar) tails. While polar groups are dissolved in water, the non-polar groups can adhere to the contaminants on skin through London Dispersion Force (a kind of van der waal's Force).
• They form clusters together called micelles around the contaminants, separate them from the surface they are attached to, so they can be easily washed off the surface.