20. The Variety of Organic         Compounds   Previous PageNext Page
        Phenols, Aromatic Alcohols

Their properties are very different: The cresols are acids, the benzyl compound is an alcohol, and anisole is an ether. The way in which atoms are connected to form a molecule is critically important to the chemical properties of the molecule. The properties of the five molecules are listed with their structures ont he previous page. All the molecules except anisole are polar because a hydrogen atom is bonded to a much more electronegative oxygen atom.

Intermolecular hydrogen bonding is possible between a positively charged hydrogen on one molecule and a negatively charged oxygen on a neighbouring molecule. This increases both the boiling and melting points for these compounds in comparison with anisole, which has only van der Waals forces between the molecules.

The benzene ring makes all of these isomers soluble in benzene, but insoluble in water. As the values indicate, the cresols ionize in aqueous solution, the other isomers do not.

Shown on the right are other simple phenolic compounds,

Top right: -Napthol ( 9.34)
Bottom right: -Napthol ( 9.51)

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