Soap is just a crystal that foams. Who knew?
All soap is a crystal as you now know. Crystals are formed when acids and bases are mixed together under proper conditions. In soap the acid is the organic vegetable oils aka fatty acids. The base is potassium or sodium hydroxide and water. The acids have extra electrons to share. The base is needy for electrons. They bond and form stable structures that are not and acid and not a base. Something new is formed – a soap crystal. Done right no measurable free alkali remains in the product.