phenols

Phenols are compounds of the general formula ArOH, ). Phenols differ from alcohols in having the —OH group 1directly to an aromatic ring. Phenols are generally named as derivatives of the simplest member of the phenol. The methylphenols are given the special name of cresols. Occasionally phenols are named as hydroxy- compounds









Physical properties
The simplest phenols are liquids or low-melting solids; because of hydrogen bonding , they have quite high boiling points. Phenol itself is somewhat soluble in water.
most other phenols are essentially insoluble in water. Unless capable of producing color is present, phenols themselves are colorless, like aromatic amines, they are easily oxidized;,-phenols are colored by oxidation products.
o-nitrophenol has a much lower boiling point and much lower solubility in water than its isomers(m and p nitophenol) ; it is thi only one of the three that is readily steam-distillable.m and p isomers have very high boiling points because of intermolecular hydrogen bonding. Their solubility is due to the hydrogen bonding in water








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The holding of a hydrogen or metal atom between two atoms of a single lie is called chelation
O-Nitrophynol shows that the- NO2 and –OH goups are located exactly right for the formation of a hydrogen bond with the signal molecule . This intramolecular hydrogen bonding takes the place of intermolecular hydrogen.Therfore o-nitrophenol has a much lower boiling point and much lower solubility in water than its isomers .