Soft versus hard soap Depending on the nature of the alkali used in their production, soaps have distinct properties. Sodium hydroxide (NaOH) produces "hard soap"; hard soaps can also be used in water containing Mg, Cl, and Ca salts. By contrast, potassium soaps, (derived using KOH) are soft soap. The fatty acid source also affects the soap's melting point. Most early hard soaps were manufactured using animal fats and KOH extracted from wood ash; these were broadly solid. However, the majority of modern soaps are manufactured from polyunsaturated triglycerides such as vegetable oils. As in the triglycerides they are formed from the salts of these acids have weaker inter-molecular forces and thus lower melting points. Lithium soaps Lithium derivatives of 12-hydroxystearate and other fatty acids are important constituents of lubricating greases. In lithium-based greases, lithium carboxylates are thickeners. "Complex soaps" are also common, these being combinations of more than one acid salt, such as azelaic or acetic acid. Fire extinguishers Fires involving cooking fats and oils (classified as class K (US) or F (Australia/Europe/Asia)) burn hotter than most flammable liquids, rendering a standard class B extinguisher ineffective. Such fires should be extinguished with a wet chemical extinguisher. Extinguishers of this type are designed to extinguish cooking fats and oils through<unk> . The extinguishing agent rapidly converts the burning substance to a non-combustible soap.
Saponification
Sterilization 
Mutagen
Detoxification
Bioaccumulation
Chelation
Fragmentation 
Hydrolysis