Chapter 21, Problem 74A

Interpretation Introduction

Interpretation:

The structural characteristics that all aromatic hydrocarbons share needs to be determined.

Concept introduction:

The ring structures of the compound having uncommon stability due to delocalized pi electron density shared in between all the carbon atoms of the ring is said to be an aromatic compound.

Explanation of Solution

The compounds that contain alternate single and double bonds in the chemical structure and are planar that is all the sp² hybridized atoms are in the same plane, are said to be aromatic in nature. All aromatic compounds follow Huckel's Rule, which is:

$\left(\text{4n+2}\right)\text{ = π electrons}$

where n is non-negative integer.

The aromatic compounds can be neutral, cationic or anionic molecule.

Thus, the structural characteristics that all aromatic hydrocarbons share is:

• All have rings with delocalized electrons.
• Have stronger bonds due to delocalization of electrons.
• They are planar.