After this chapter students will be able to do the nomenclature for alkanes, alkenes, alkynes as well as the aromatic hydrocarbons. Some of the other topics covered are a mechanism of electrophilic substitution, nitration, sulphonation, halogenation, Friedel Craft's alkylation and acylation, directive influence of functional group in mono-substituted benzene. Carcinogenicity and toxicity.