Aromatic hydrocarbons

Definition

Aromatic hydrocarbons are a class of compounds characterized by the presence of one or more benzene rings. They are known for their stability and unique chemical properties due to resonance.

5 Must Know Facts For Your Next Test

1. Aromatic hydrocarbons contain conjugated pi-electron systems that create a ring structure, typically benzene.
2. They follow Huckel's rule, which states aromaticity is achieved with (4n+2) pi electrons in the ring.
3. Aromatic hydrocarbons are less reactive than alkenes due to delocalized electrons, providing stability.
4. Common examples include benzene, toluene, and naphthalene.
5. They play a crucial role in organic chemistry and biochemistry, including the structure of DNA bases.

Review Questions

• What structural feature defines an aromatic hydrocarbon?
• Explain Huckel's rule in the context of aromaticity.
• Why are aromatic hydrocarbons generally more stable than alkenes?

Related terms

Aliphatic Hydrocarbons: Hydrocarbons that do not contain aromatic rings and can be either saturated or unsaturated.

Benzene: A simple aromatic hydrocarbon with the formula C6H6, forming a six-membered ring with alternating double bonds.

Resonance: The concept where electrons are delocalized within molecules that have conjugated bonds, contributing to stability.