The chemical reaction which is used to produce or form soap is know conveniently as the saponification reaction in which case the esters or fat (glyceryl ester) are used in a solution where lye is combined with water and mixed with an alkali and ester similar to sodium hydroxide or potassium hydroxide to produce a free alcohol (glycerin) and a carboxylate salt, to summarize alkaline hydrolysis of a oil or fat to produce soap. Ancient men have produce soaps from cooking animal fat when the fat or oil dripped into the fire it produced a chemical reaction when the ester combined and reacted with the wood wash to form the soap after a period of time.
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