Chapter U2.40, Problem 5E

Interpretation Introduction

Interpretation : Information required in determining the smell of a compound which is made of molecules that had a stringy three dimensional shape is to be explained.

Concept Introduction :

The smell of a compound is mainly due to the functional groups and shape of the molecule. A molecule may be long and stringy, ball shaped or pan shaped. The functional groups may be carboxyl, amine, ester, hydroxyl or ketone.

Explanation of Solution

Smell is determined by the functional group present in the molecule and also the shape of the molecule.

If it is given that the molecule has a stringy three dimensional shape, the compound may have a fishy smell or a sweet smell or putrid smell. If the functional group present in the molecule is known one can predict the smell accurately.

For example if the functional group present is:

• Amine, the molecule will have fishy smell
• Carboxyl, the molecule will have putrid smell
• Ester, the molecule will have sweet smell
• Hydroxyl, the molecule will have sweet smell.
• Ketone, the molecule will have sweet smell.

Conclusion

The chemistry of smell is very complex. From shape of a molecule one can predict the smell of the molecule and the functional group in the molecule helps to confirm the smell.