Bithional added to soaps to impart antiseptic properties and to reduce the odour produced by bacterial decomposition of organic matter on skin.
What is soap?
Soaps are water-soluble sodium or potassium salts of fatty acids. It works by breaking up the oil into smaller drops so that it can mix with the water. The principle of soap works because soap is made up of molecules with two very different ends. One is hydrophilic, and it is this end of the soap molecule that loves water. This is the salt end of the soap; it is ionic and soluble in water. The hydrophobic end does not mix with water and is therefore repelled by it.
- Since soap molecules have both properties of non-polar and polar molecules, the soap acts as an emulsifier.
- The hydrophilic part of the soap molecules points out, whereas the hydrophobic parts group together on the inside.