Benzene and cyclohexane are both hydrocarbons, but they differ significantly in their structure and properties.
Structure: Benzene is an aromatic hydrocarbon with a planar cyclic structure composed of six carbon atoms arranged in a ring, with alternating double bonds. This configuration gives benzene its distinctive stability known as resonance. On the other hand, cyclohexane is a saturated hydrocarbon that consists of six carbon atoms in a ring, all bonded by single bonds, making it a non-aromatic compound.
Chemical Properties: Due to its pi-electron system, benzene is highly stable and tends to undergo electrophilic substitution reactions rather than addition reactions. Cyclohexane, being saturated, typically participates in addition reactions since it doesn’t have the resonance stabilization found in benzene.
Physical Properties: Benzene is a colorless liquid with a characteristic sweet odor, and it is known for its solvent properties. It has a boiling point of about 80°C. Cyclohexane is also a colorless liquid, but it has a less sweet odor compared to benzene and a boiling point of about 81°C. Cyclohexane is commonly used as a solvent as well, but it is less toxic than benzene.
In summary, the primary differences between benzene and cyclohexane lie in their molecular structure, stability, and reactivity, which are a result of benzene’s aromatic character contrasted with cyclohexane’s saturated nature.