Since soap molecules have both properties of non-polar and polar molecules soap can act as an emulsifier. An emulsifier is simply an additive that helps two liquids mix. When greasy dirt, fat, or oil is mixed with soapy water, the soap molecules arrange themselves into tiny clusters called micelles. The water-loving hydrophilic head of the soap molecules sticks to the water and points outwards, forming the outer surface of the micelle.
The oil-loving hydrophobic tail sticks to the oil and trap oil in the center where it can't come into contact with the water. With the oil trapped safely in the center, the micelle is soluble in water. As the soapy water is rinsed away the greasy dirt goes along with it. Ever wonder why it is easier to clean dirty, greasy hands and other things in hot or warm water rather than cold water? It is because the fats and oils soften or melt in hot water, which allows them to attach more readily to the hydrophobic end of the soap molecule.
In turn, that makes it easier to rinse away. Soap is a natural surfactant. A surfactant is any substance that tends to reduce the surface tension of a liquid in which it is dissolved. Almost all cleansing products are based on surfactants. Surfactants not only reduce the surface tension of the water but the way they are constructed with one hydrophilic end and one hydrophobic end makes them compatible with both water and oils.
When water and oil are mixed they separate. Hydrophilic and hydrophobic compounds just don't mix. The cleansing action of soap is determined by its polar and non-polar structures in conjunction with an application of solubility principles.
The long hydrocarbon chain is non-polar and hydrophobic repelled by water. The "salt" end of the soap molecule is ionic and hydrophilic water soluble. When grease or oil non-polar hydrocarbons are mixed with a soap- water solution, the soap molecules work as a bridge between polar water molecules and non-polar oil molecules.
Since soap molecules have both properties of non-polar and polar molecules the soap can act as an emulsifier. An emulsifier is capable of dispersing one liquid into another immiscible liquid. The soap will form micelles see below and trap the fats within the micelle. Since the micelle is soluble in water, it can easily be washed away.
When you mix soap into the water the soap molecules arrange themselves into tiny clusters called 'micelles'. The water-loving hydrophilic part of the soap molecules points outwards, forming the outer surface of the micelle. The oil-loving hydrophobic parts group together on the inside, where they don't come into contact with the water at all.
Micelles can trap fats in the center. Multiple Choice Questions. Water is considered a polar molecule because a the molecule has a net positive charge b the molecule has a net negative charge c the molecule has a net zero charge d the ends of the molecule have partial negative and positive charges. Soap is formed from: a two hydrophobic compounds b a physical change when fats are heated c two hydrophilic compounds d oils or fats by reacting them with an alkali 3.
Try this experiment to find out. Washing up liquid is a kind of soap. Normally, oil and water don't mix, so they separate into two different layers. Soap breaks up the oil into smaller drops, which can mix with the water.
It works because soap is made up of molecules with two very different ends. One end of soap molecules love water - they are hydrophilic. The other end of soap molecues hate water - they are hydrophobic. Hydrophobic ends of soap molecule all attach to the oil.
Hydrophilic ends stick out into the water. This causes a drop of oil to form:. These drops of oil are suspended in the water. This is how soap cleans your hands - it causes drops of grease and dirt to be pulled off your hands and suspended in water. These drops are washed away when you rinse your hands. Planet Science.
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