Question

You have learned that the liver is an important part of the digestive system. This organ secretes a liquid called bile. Bile is used by the small intestine to break down fats into an emulsion. An emulsion is a liquid with drops of fat or oil. In this experiment you will see how an emulsion is formed.
Why do you think it is necessary to break up the fat into tiny droplets?

How could you explain why soap is able to clean the oil and dirt off our bodies?

Answer 1

1- If the droplets accumulate, it will become a mass and probably stick to the body for a long time, causing obesity and poisoning.
2-Even if some of the dirt is removed when we wash our hands with only water, our hands are not completely cleaned because the water molecules can not solve the oil and so on. In order for one substance to solve the other, these substances must have a similar structure. In other words, polar substances dissolve in polar solvents whereas apolar substances dissolve in apolar solvents. Polar water (H2O) molecules composed of hydrogen and oxygen atoms can not solve apolar impurities which are usually composed of oil and similar substances. For this reason we need a sabbatical to clean our hands. Soap molecules are composed of two parts, polar and apolar. In the soap molecule, the head is polar and the tail part is apolard. While washing our hands, the apolar parts of the soap's long hydrocarbon chains are attached to the apolar pollutants and even surround them, and the polar parts interact with the water molecules. The oil particles wrapped around are separated from each other and dispersed in water. Thus, the oil molecules separated from the surface easily flow together with the water.

Answer 2

1) It is necessary to break up the fat into tiny droplets, because in that way, it is easier for them to be digested and consumed. If the droplets build up, it will become a mass, and most likely be stuck inside the body for long periods of time, resulting in obesity, and toxication.

2) Soap is able to clean the oil and dirt off our body, because it breaks up the oil and impurities into smaller 'drops', which is more easier to be washed off through the soap mixing with water

hope this helps