How does phenol differ from benzene?

Phenol and benzene are both aromatic compounds, but they have distinct structural and chemical properties. Here are the key differences between them:

Structure:

Benzene: Benzene (C₆H₆) is a simple aromatic hydrocarbon consisting of a six-carbon ring with alternating double bonds (resonance structure), with each carbon atom bonded to a single hydrogen atom.
Phenol: Phenol (C₆H₅OH) has a similar benzene ring structure, but one of the hydrogen atoms is replaced by a hydroxyl group (-OH).
Chemical Formula:

Benzene: C₆H₆
Phenol: C₆H₅OH
Functional Group:

Benzene: No functional group apart from the aromatic ring itself.
Phenol: Contains a hydroxyl group (-OH) attached to the aromatic ring.
Physical Properties:

Benzene: Benzene is a colorless, volatile, and flammable liquid with a sweet smell. It is less dense than water and immiscible with it.
Phenol: Phenol is a white crystalline solid or a colorless liquid with a distinct odor. It is moderately soluble in water and can form hydrogen bonds due to the presence of the -OH group.
Acidity:

Benzene: Benzene is not acidic; it is a neutral compound.
Phenol: Phenol is weakly acidic due to the presence of the hydroxyl group, which can donate a proton (H⁺) to form phenoxide ion (C₆H₅O⁻).
Reactivity:

Benzene: Benzene undergoes electrophilic aromatic substitution reactions (e.g., nitration, halogenation, sulfonation) but is generally less reactive than phenol.
Phenol: Phenol is more reactive than benzene in electrophilic aromatic substitution reactions due to the electron-donating effect of the hydroxyl group, which activates the ring towards substitution.
Uses:

Benzene: Used as an industrial solvent, in the production of various chemicals, and as a starting material for the synthesis of numerous compounds.
Phenol: Used in the manufacture of plastics (e.g., Bakelite), pharmaceuticals, dyes, and as a disinfectant and antiseptic.
In summary, while both phenol and benzene share a common aromatic ring structure, the presence of the hydroxyl group in phenol significantly alters its physical, chemical, and reactivity properties compared to benzene.