252

Smells | REVIEW

Smell chemistry is an active area of research. Scientists are still refining theories about how smell works. However, one thing is clear: Smell is all about molecules. To understand smell, it is important to understand what molecules are and how they are put together.

The smell of a compound is greatly dependent on its composition and structure. This is true of other molecular properties besides smell. You do not smell some molecules because they are too large or heavy to become airborne, or because they are nonpolar and do not stick in receptor sites. Other molecules have a type of smell that depends on what atoms or functional groups are present. The smell of a molecule may also depend on the shape of the entire molecule.

By exploring the topic of smell, you have studied covalent bonding and the general rules governing how atoms come together to form the amazing structures called molecules.