MCQ Detailed View

Benzyl alcohol is an important aromatic alcohol with the molecular formula C₆H₅CH₂OH. It consists of a benzene ring (C₆H₅-) attached to a -CH₂OH group. This makes it a primary aromatic alcohol, because the hydroxyl group (-OH) is directly bonded to a carbon atom that is attached to the benzene ring through a methylene (-CH₂-) bridge.

Let’s carefully examine the options:

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  C₆H₅OH is phenol, not benzyl alcohol. In phenol, the hydroxyl group is directly attached to the benzene ring, which changes its properties and reactivity compared to benzyl alcohol.

  
  


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  C₆H₅CH(OH)₂ is a hypothetical compound, sometimes considered an unstable hydrate form, and it does not represent benzyl alcohol.

  
  


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  C₆H₅CH₂OH is the correct structure of benzyl alcohol. It is a colorless liquid with a mild pleasant aroma, often used as a solvent, preservative, and intermediate in organic synthesis.

  
  


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  C₆H₅COOH is benzoic acid, which contains a carboxyl group (-COOH) instead of a hydroxyl group. It is an aromatic carboxylic acid, not an alcohol.

  
  

Benzyl alcohol is widely used in chemistry and industry. In the laboratory, it is applied as a solvent for inks, paints, and resins. In pharmaceuticals and cosmetics, it serves as a preservative and bacteriostatic agent. It is also an intermediate in the manufacture of esters and other derivatives used in perfumes and flavors.

The difference between phenol and benzyl alcohol is very important. While phenol is acidic and can ionize in water, benzyl alcohol behaves more like a typical alcohol with weaker acidity and different chemical behavior.

Thus, among the given compounds, C₆H₅CH₂OH is correctly identified as benzyl alcohol.