What is meant by soap? Write its preparation.

Soap is a sodium or potassium salt of fatty acid (stearic acid, oleic acid, palmitic acid). Sodium salt is present in washing soaps and potassium salt is present in bathing soaps.

Preparation of Soap- When vegetable oil (groundnut oil) or animal fat heated with sodium hydroxide (NaOH) then sodium salt of fatty acid and glycerol are formed. This process of preparing soap is called saponification.

Vegetable oil or animal fat + Sodium hydroxide Glycerol + Sodium salt of fatty acid (soap)