How does Soap Clean Things?

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Soap is used for washing. It makes the grease dissolve in water, because it is usually the grease that holds dirt and dust stuck on to the clothes. Ordinary water does not remove dirt from things because the grease and water cannot mix. Soap is made of long, thin molecules that attach themselves to water molecules at one end and to grease molecules at the other end. The soap molecules, thus, link the water and grease molecules, so that the grease Soap is made by heating fat or vegetable oil with a strong alkali, such as sodium hydroxide (Caustic Soda).

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