Rings, Polymers and Analysis 1.5 / 5 based on 2 ratings ? ChemistryPolymersA2/A-levelOCR Created by: JoshCreated on: 28-08-12 16:22 Arenes have considerable energetic stability because of the delocalised π bonding electrons. Arenes require much more vigorous reaction conditions than alkenes to undergo addition reactions because of this extra stability. 1 of 5 Arene chemistry is dominated by electrophilic substitution reactions that enable arenes to retain their delocalised π electrons. Hydrogen atoms on the benzene ring may be replaced by a variety of other atoms or groups including halogen atoms and nitro (–NO2) groups. 2 of 5 The variety of substitution reactions on benzene provides access to many useful compounds. These include medicines, dyes, explosives and polymers 3 of 5 Phenols are weakly acidic and form salts. These are called phenoxides, and also form water on reaction with sodium hydroxide. 4 of 5 The -OH group enhances the reactivity of the benzene ring towards electrophiles. Bromine water is decolourised by phenol, producing a white precipitate of 2,4,6-tribromophenol. 5 of 5
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