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A, , Benzene is a colourless liquid with a characteristic smell, insoluble in water, but soluble in, organic solvents such as alcohol and ether. It is inflammable and burns with a sooty flame., , Benzene: Electrophilic Substitution Reactions, , If a substitution reaction is initiated by an electrophile, it is called an electrophilic substitution, reaction. Common electrophilic substitutions are:, , , , Halogenation, , Sulphonation, , Nitration, , Friedel — Crafts Alkylation, , Friedel — Crafts Acylation Reaction, , All types of electrophilic substitution reactions proceed via the following three steps:, , Generation of the electrophile, Formation of the carbocation intermediate, Removal of the proton from the carbocation intermediate, , Benzene: Directive Influence of Substituents, , The nature of the group in monosubstituted benzene decides the position of the new incoming, electrophile on the benzene ring; this is known as the directive influence of a group in, monosubstituted benzene., , This influence could be either ring activating or deactivating., Ring activating groups are ortho and para directing groups., , Examples of ortho and para directing groups are — NH>, -NHR, -NHCOCH3,