Sometimes we wonder while washing our hands that what is the soap made of? How does it clean the dirt from our body? Learn here, which ingredients make soap.
The first soaps were probably the saps of certain plants, such as the Soap Plant (Chlorogalum pomeridianum), whose roots can be crushed in water to form a lather, and used as a shampoo. Later, people learned that fats would react with alkalies in the ashes left over from a fire to produce saponified compounds such as sodium stearate and the related potassium stearate.
Today, what soap does contain, however, does a very effective job of cleaning for several reasons. To make soap, sodium or potassium salts must be derived from fatty acids by combining them with an alkali (like potassium or sodium hydroxide) in a process scientists call saponification.
The resulting soap molecules consist of a hydrocarbon chain that has a sodium or potassium atom at the end. The hydrocarbon end of the chain is hydrophobic, which means it repels water. The sodium or potassium end of the chain is hydrophilic, which means it attracts water.
This unique structure gives soap its cleaning power. When your hands are dirty, it's usually because oils have attracted dirt molecules, causing them to stick to your hands.
When you wash your hands with soap, the hydrophobic ends of the soap molecules attract the oily dirt, forming a drop of oil surrounded by soap molecules with their hydrophilic ends sticking outward. When you rinse your hands, the hydrophilic ends of the soap molecules allow the suspended drops of oil to be washed away.