which part of a soap is responsible for its ability to dissolve fats and oily dirt?
Best Answer: Soaps are the sodium or potassium salts of fatty acids. The tails of the soap molecules are chemically equivalent to fat or oil, i.e. they are both hydrophobic and non-polar. Therefore, soap can dissolve in oil. The heads of soap molecules, however, are hydrophilic and ionic in character. This allows them to dissolve in ionic and polar substances, e.g. water. When oily dirt is immersed in a soap solution, the tails attach themselves to the oil.