Chapter U2.40, Problem 4E

Interpretation Introduction

Interpretation : The information that can be obtained about the molecule by just knowing it has a sweet smell needs to be explained.

Concept Introduction :

There are different types of smells. Each smell is due to a different type of molecule. The smell is mainly due to the functional groups and shape of the molecule.

Answer to Problem 4E

A sweet smelling molecule is generally long and stringy thus, the shape of the molecule can be assumed from its sweet smell. The functional group present in the molecule cannot be assumed by its sweet smell. This is because two different functional groups may have sweet smell.

Explanation of Solution

Smell is determined by the functional group present in the molecule and also the shape of the molecule. A sweet smelling compound has two oxygen atoms. Also, a sweet smelling molecule is generally long and stringy.

One cannot assume the functional group present in the molecule because phenyl acetate, pentatonic acid and propyl acetate all contain 2 O atoms but the functional group in pentatonic acid is different.

Conclusion

The chemistry of smell is very complex. From smell of a molecule one can predict the overall shape of the molecule but, one cannot predict the functional group present in the molecule.